HSE 1101 of home and garden pesticide containers

3

There are a large number of incinerators in the UK, ranging from small laboratory incinerators to large operations that burn household waste (Defra 2007). Incinerators burn waste at very high temperatures (> 850 °C) which turns the waste to ashes, flue gas and heat reducing the initial volume of the waste by ~80-85%. The heat can be used to recover energy in form of heat or electricity, which is called Energy from Waste (EfW) or Waste to Energy (WtE). Incineration produces two forms of solid residue – fly ash, which is fine particulate matter carried with flue gases, and bottom ash, which falls from the fire-grate. They constitute, between them, about one quarter to one third of the total pre-combustion weight of waste. Flue gas must be cleaned of gaseous and particulate pollutants before being released to the atmosphere. Fly ash or air pollutant control residues (APCR) are disposed of as to or other treatment facilities. Bottom ash is either disposed of as non-hazardous waste and goes to after metals (mainly ferrous metals) have been recovered or recycled. Additionally waste water is produced as part of the pollution control process.

3.1 The incineration process Waste delivery and raw materials handling Different types of waste (depending on the plant permit) are delivered into the tipping hall by appropriate vehicles. The delivery vehicles are weighed on entry into the site, after which they tip their load into a capacity bunker. The vehicles are re-weighed on exit to calculate the amount of waste delivered to the site. Waste types normally include (MSW), non-hazardous commercial, industrial or trade waste, but also small amounts of hazardous . The tipping hall is operated under negative pressure to minimise escape of odours, dust or . The vehicles tip into a waste storage bunker from where the grab cranes mix the waste in the bunker to obtain a more controlled calorific value and to remove any unsuitable items. Then the grab cranes load the waste into a hopper from where it is pushed into the incinerator by hydraulic rams or falls by gravity onto the inclined rocking grate. In some plants the waste might be lifted using mechanical shovels into the feed hopper.

Although less common, an incineration plant can also have a waste separation area where waste is sorted by size. In this case different waste fractions are further sorted and collected for processing into refuse-derived-fuel (RDF), or , or for recycling elsewhere; ferrous metals are removed by a magnetic separator and stored in a 'ferrous metals' area. Non- ferrous metals are removed by a separator and stored in a 'non-ferrous metals' area. Dense plastics will be separated off and stored for recycling.

Combustion unit and boiler The waste is burned on a grate, with preheated air being injected above and below the grate. Combustion air is drawn from the tipping hall and boiler hall to reduce odours and dust levels in these areas and fed to the furnace via an air pre-heater. Burners, mainly fired on gas oil or low-sulphur diesel, are installed to maintain temperatures above the 850 °C threshold.

The secondary air is drawn in part from re-circulated flue gas in order to reduce the formation of oxides of nitrogen Ammonium hydroxide can be injected into the furnaces to reduce emissions of nitrogen oxides (this technique is known as selective non-catalytic reduction or SNCR).

The hot gases are maintained at a minimum temperature of 850 °C for 2 seconds in the presence of excess oxygen in the combustion chamber. The oxygen concentration and the

1

HSE 1101 Recycling of home and garden pesticide containers

temperature should be carefully controlled to ensure effective combustion and to minimise the formation of pollutants, including dioxins.

Residues/ash handling system Burnt out bottom ash residues are discharged from the lower end of each grate into a water- filled ash discharger, where it is quenched. The bottom ash is transported by moving belts into dedicated bunkers. Ferrous metals are removed from the bottom ash and then recycled. The bottom ash is removed from site for disposal or processed into an approved aggregate material e.g. for road building and construction.

Residues from the flue gas treatment process are discharged in an enclosed system into e.g. double skinned heavy duty bags prior to removal from site for treatment and disposal.

Flue gas treatment/air pollution control (APC) equipment Flue gases pass from the boiler to the gas cleaning equipment. The cooled gases enter a reaction chamber where lime dust and activated carbon are injected to neutralise acid gases and absorb (primarily) dioxins, volatile organic compounds (VOCs) and mercury. Nitrogen oxides (NOx) abatement can be achieved by the use of both flue gas recirculation (FGR) and selective non-catalytic reduction (SNCR) using ammonium hydroxide. The exhaust gases and reagent particles are then filtered in a fabric or bag filter to remove particulate matter and other pollutants. The filters are regularly cleaned, and the collected end product is stored appropriately in closed containers. The APC residue is disposed of in a suitably- licensed landfill site. The cleaned gas then discharges to atmosphere via a stack/chimney. Continuous emission-monitors analyse the exhaust gases from the chimney to include particulates, sulphur dioxide, oxides of nitrogen, carbon monoxide, hydrogen chloride, TOC and ammonia.

Energy recovery Heat from the burning of the waste is used in the heat-recovery-boiler to raise steam which, in turn, is used in the steam-turbine-driven-alternator to generate electricity which is used for powering plant auxiliaries and the surplus is exported to the national grid. Some plants also have the capacity to export heat, in the form of high pressure hot water, to e.g. local factories.

3.2 Operating incineration plants and estimated waste incineration volumes in the UK Based on information available on the internet and on annual performance reports, 24 operational EfW incinerators in were identified excluding incinerators in planning or decommissioned incinerators1.

It has to be noted that the number of operational municipal incinerators in the UK is constantly changing due to building and commission of new incinerators, decommissioning of old incinerators as well as closing/re-opening of existing incinerators and therefore reliable information is difficult to obtain. Reports from Defra 2007 and Tolvik consulting 2011 therefore show a discrepancy of operating incinerators (see Table 2 and Table 3).

Table 1 provides an overview of the identified incinerators and the volume of waste incinerated each year, also detailing the volume of residues based on the latest available annual performance reports. Whilst the data are now a little dated, they still provide a good estimate of total waste volumes incinerated as well as produced residues by incinerators in the whole of the UK. Based on this data we assume that a total of ~4,325,021 Tonnes of

1 http://ukwin.org.uk/resources/table/; http://ukwin.org.uk/resources/incinerator-reports/; https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/181825/pb13889- incineration-municipal-waste.pdf.pdf

2

HSE 1101 Recycling of home and garden pesticide containers

waste are incinerated in the UK per annum leaving behind a total of 127,822 Tonnes of air pollution control residues (APCR) and 717,157 Tonnes of bottom ash for landfill or additional .

There has also been a report by Tolvik consulting (Tolvik consulting 2011) evaluating the performance of the 19 EfW plants operated in England and Wales. For the years 2008 and 2009 the volume of incinerated waste by these plants are given in Table 2. According to Tolvik’s data 3,266,512 and 3,490,079 tonnes of waste have been incinerated in England and Wales in 2008 and 2009, respectively. For all the analysed EfWs, Tolvik report that municipal solid waste (MSW) was the principle feedstock (~98% of processed waste being MSW). Tolvik further state that, of the 16 facilities analysed, 12 reported bottom ash tonnages of between 19.5% and 22.0% of total waste throughput. Half the facilities reported that the bottom ash was recycled, whilst for the rest, where it was landfilled in 2008, nearly all the annual reports pointed to plans to move to bottom ash recovery. Similarly, for Air Pollution Control (APC) Residues, the figures reported were all in the range of 2.5 to 3.8% of waste feed. All reported ultimate landfill disposal although some detailed the pre-treatment provided.

Table 2 shows incinerators and waste incineration capacities (tonnages per year) for the UK and Table 3 gives output values for solid residues and gaseous emissions in % from incinerator technologies, both tables taken from Defra (2007).

3

HSE 1101 Recycling of home and garden pesticide containers

Table 1 Operational waste incineration plants in the UK.

Plant Type Operator Hazardous Non-hazardous waste Waste inc. Year waste (tonnes) ACPR (tonnes) bottom ferrous metals ash metals recov. recov. (tonnes) (tonnes) (tonnes) Allington EfW Kent EnviroPower Ltd 15619 13189 4812 1861.15 132540.63 2008 Baldovie (Dundee) EfW Dundee Energy Recycling Ltd (DERL) 120000 capacit y Bolton EfW Viridor Ltd 2457.86 18724.61 1861.15 84939 2009 Chineham EfW Veolia 2904 20593 1662 98562 2011 Colnbrook (Berkshire) EfW Grundon Waste Managem. Ltd & Viridor 383716 2010 Coventry EfW The Coventry & Solihull Waste Disp. 7519 52565 7925 245187 2009 Comp. Ltd Dudley EfW MES Environmental Ltd 3286 1288 91362 2011 East Kent HTI Augean waste network 10000 capacit y Eastcroft (Nottingham) EfW WasteNotts Ltd 4898 30446 2915 159268 2011 Edmonton () EfW LondonWaste Ltd 16478 86301 16478 521246 2008 Ellesmere (Cheshire) HTI Veolia 10000 capacit y Fawley HTI Pyros Environ. Ltd & Tradebe Fawley Ltd 1700 4658 26775 2009 Grimsby EfW Newlincs Development Ltd 2342 9976 1046 54744 2008 Huddersfield EfW Kirklees 5768 24571 2816 135484.32 2009 Isle of Man EfW SITA Waste Ltd 1817 12055 815 54142 2009 La Colette (Jersey) EfW Jersey Transport & Technical Services 126000 capacit y Marchwood EfW Veolia ES Hampshire Ltd 5984 45693 3468 201031 2011 Neath Port Talbot EfW Neath Port Talbpt Ltd 535 2376 9041 2008 Newhaven EfW Veolia ES Southdowns Ltd 3232 18001 1527 92678 2011 Portsmouth EfW Veolia ES Ltd 5442 41060 4932 201578 2011 SELCHP (Lewisham) EfW Veolia ES Selchp Ltd 12896 98005 7281 426872 2007 Sheffield EfW Veolia ES Sheffield Ltd 4732.41 41099.1 6390.78 207000 2011

4

HSE 1101 Recycling of home and garden pesticide containers

Plant Type Operator Hazardous Non-hazardous waste Waste inc. Year waste (tonnes) Shetland (Lerwick) EfW Shetland Heat Energy & Power Ltd 22098 2009 Stoke on Trent EfW MES Environmental 5914 38162 2291 178917 2011 Teeside EfW SITA Waste Ltd 10763 55068 6409 256609 2009 Tyseley (Birmingham) EfW Veolia ES Ltd 10124 81400 3406 366414 2010 Wolverhampton EfW MES Environmental Ltd 3411 23214 829 108817 2010 Total 127822.27 717156.71 31316.15 48696.93 4325020.9 5

5

HSE 1101 Recycling of home and garden pesticide containers

Table 2 Tonnages of incinerated waste for 2008 & 2009 in England and Wales by plant (Torvik 2011).

Tonnage Tonnage Date Installation Incinerated (2008) Incinerated (2009) Commissioned Allington 132,541 384,784 2008 Bolton 95,754 84,939 2000 Chineham 94,972 101,754 2003 Coventry 241,733 245,187 1975 Dudley 93,300 93,445 1998 Edmonton 521,246 383,153 1970 Grimsby 54,744 53,728 2003 Kirklees 87,003 136,000 2002 Marchwood 190,711 188,244 2006 Nottingham 158,459 116,444 1971 Portsmouth 201,569 196,797 2006 SELCHP 421,648 395,641 1994 Sheffield 140,000 219,976 2006 Stoke 162,145 181,339 1998 Tees Valley 204,327 256,609 1998 Tyseley 359,129 342,048 1996 Wolverhampton 107,231 109,991 1998 Total 3,266,512 3,490,079

Table 3 Incinerators and waste incineration capacities taken from Defra, 2013.

Incinerator Plant (T/y) Established Energy recovery (MWe) Edmonton, London 675,000 1975 55 SELCHP, London 420,000 1994 35 Tysesley, Birmingham 350,000 1996 25 Cleveland 390,000 1998 30 Coventry 240,000 1975 17.7 Stoke 200,000 1997 12.5 Marchwood 165,000 2004 17 Portsmouth 165,000 2005 17 Nottingham 160,000 1973 14.4 Sheffield 225,000 2006 17 Wolverhampton 110,000 1998 7 Dudley 105,000 1998 7 Chineham 102,000 2003 7 Kirklees 136,000 2002 10 Allington 500,000 2008 43 Grimsby 56,000 2004 3.2 Lakeside, Colnbrook 410,00 2010 37 Isles of Scilly 3,700 1987 0 Bolton 130,000 1971 7 Total 3,343,700

6

HSE 1101 Recycling of home and garden pesticide containers

Table 4 Outputs from incinerator technologies taken from Defra (2013)

Quantity by Wt of Outputs State Comment original waste Potential use as aggregate replacement or non Incinerator bottom ash Solid residue 20-30% biodegradable, non- hazardous waste for disposal Metals (ferrous and non- Requires separation from 2-5% Sold for re-smelting ferrous) MSW or IBA APC residues (including fly ash, reagents and Solid residue/liquid 2-6% Hazardous waste for disposal waste water) Emission to atmosphere Gaseous Represents ~70-75% Cleaned combustion products

3.3 Incineration of pesticides and their containers Incineration of pesticides and their containers can produce toxic combustion products, which may be released to the environment and humans may be exposed to. Some of the literature reviewed is given below, but it is reiterated that information was dated and therefore could not be applied to current incineration technology with confidence.

Behaviour of plastics during incineration The prediction of toxic combustion products is a complex area as it not only depends on the substance burnt, but also on the nature of the fire and the conditions of burning. (Wakefield 2010).

Brown and Levin (1986) concluded that pyrolysis products of a given polyester are a function of temperature and atmosphere. As the temperature was increased, researchers observed a decrease in the quantity of heavier hydrocarbons with an increase in the production of CO and CO2.

Boettner et al. (1973) state that the potential hazard from compounds generated on combustion of a plastic depends on the primary structure of the polymer, the additives used in formulating the plastic, and the conditions under which it is burned. Plastics composed of only carbon and hydrogen or carbon, hydrogen and oxygen form carbon dioxide and water when completely combusted. Incomplete combustion results in production of carbon monoxide as the major toxicant, plus gaseous and condensed hydrocarbon products. The condensate may be a source of polycyclic hydrocarbon pollutants, particularly from aromatic polymers. Plastics containing nitrogen as a hetero-atom produce on complete combustion molecular nitrogen and small amounts of oxides of nitrogen, as well as carbon dioxide and water. On incomplete combustion hydrogen cyanide, cyanogens, nitriles and ammonia may form in addition to hydrocarbon gases. Any liquid condensate formed may be composed of a variety of organic nitrogen compounds as well as hydrocarbons. Nitrogen compounds are more sensitive than other combustion products to changes in combustion conditions. Generally the more incomplete the combustion, the more ammonia and cyanide will form. Plastics containing halogen or sulphur heteroatoms form acid gases such as hydrogen chloride (HCl), hydrogen fluoride (HF), and sulphur dioxide (SO2) on complete combustion in addition to carbon dioxide and water, and can form organic halogen or sulphur compounds on incomplete combustion. These compounds present air pollution, incinerator corrosion, and toxicity problems (Boettner et al. 1973).

Combustion of poly ethylene terephthalate Braun and Levin (1986) have reviewed the literature for combustion products of polyesters and found that the combustion of a silicone rubber/ poly(ethylene terephthalate) cable insulation material in an inert atmosphere of helium at 800°C produced CO, CO2, CH4, ethylene, propylene, butadiene, benzene and toluene combustion products, all of which

7

HSE 1101 Recycling of home and garden pesticide containers

were attributed to the poly(ethylene terephthalate). They also identified a study in which poly(ethylene terephthalate) was exposed to temperatures ranging from 283 to 306°C in nitrogen atmospheres. Under isothermal conditions this polymer slowly decomposed into low molecular weight fragments such as C2H4, 2-methyldioxolan, CH4, C6H6 and CH3CHO in addition to CO, CO2, and H20. The primary decomposition product was CH3CHO. The use of air as the decomposition atmosphere also resulted in the decreasing production of high molecular weight fragments with increasing temperature. An increase in the production of CO, CO2, H2O and CH4 was observed. At high temperatures (450-500 °C) CH4 would also decompose to H2O and CO2.

The presence of flame retardant additives, such as bromine and chlorine, produced halogenated combustion product. The use of phosphorus and bromine in the same flame retardant finish increased the concentration of low molecular weight compounds. This can be relevant for the incineration of pesticide containers as many pesticides contain halogens and even if containers are rinsed appropriately a pesticide rest will remain.

Sovovoa (2008) combusted samples of PET material in a furnace corresponding to the German standard DIN 53 436 at temperatures of 500°C and 800°C (in an air flow) as well as uncontrolled burning in air. Carbon dioxide, methane, ethylene, acetylene, formaldehyde (methanal) and acetaldehyde (ethanal), water, methanol, acetone, benzene, terephthalic acid, styrene (ethenylbenzene), ethanol, propane, toluene (methylbenzene), xylene (dimethylbenzene), ethylbenzene, naphthalene, biphenyl and phenol concentrations were detected. The results of this study show that uncontrolled burning in air leads to products which are similar to those from thermal decomposition in a quartz furnace at the temperature of 500°C, i.e. below the PET inflammation point of 600°C. In comparison, the products of PET combustion at 800°C contain mainly carbon oxides, water and the heavier hydrocarbons in significantly lower concentrations. The only two cases where concentration increased at the higher temperature were biphenyle and naphthalene.

Combustion of high-density polyethylene Boettner (1973) show the results of the combustion of high-density PE at 1000 °C. The high- density material differs from the low-density material in having less branching of the chains. They state that combusting polyethylene to carbon dioxide and water is not difficult, but incomplete combustion leads to many hydrocarbon products. In the study all tested HDPE plastics completely decomposed at 500 to 550°C in a single degradation step. Infrared analysis of PE combustion gas showed carbon dioxide, carbon monoxide, and methane to be present along with other hydrocarbons as well as ethylene, ethane, methanol, and acetaldehyde. Carbon monoxide was the only acutely toxic combustion product identified.

Combustion of polyamide Braun and Levin (1987) reviewed the literature on combustion of polyamides, however, the review was limited to aliphatic polyamides (nylons) and excludes aromatic polyamides. Typical pyrolysis products from a broad range of nylons do not appear to differ greatly. Many of the decomposition products detected in vacuum pyrolysis experiments appear as products of thermal degradation in inert and air atmospheres. In air, a general reduction in the quantities of heavier hydrocarbons is noted along with an increase in the production of CO, C02, H20, NH3, HCN and NOx (Braun and Levin 1987).

8

HSE 1101 Recycling of home and garden pesticide containers

Combustion of ethylene vinyl alcohol No specific scientific literature could be identified on combustion of ethylene vinyl alcohol during the time frame of this project.

Behaviour of pesticides during incineration Similar to the combustion of plastics, the potential hazard from compounds generated on combustion of pesticides depends on the primary structure of the pesticide, and the conditions under which it is burned. Additionally to the typical combustion products of organic substances such as CO2, CO, water vapour etc., toxic combustion products of the incineration of pesticides depending on complete or incomplete combustion and the type of pesticide can include cyanide, phosphor pentoxide, hydrochloric acid, nitrogen oxides, and organochlorine compounds as well as other halogen containing compounds among others.

Whether or not pesticides can be properly incinerated depends on the type of pesticide, the kind of incinerator, and the gas cleaning system. There has been some information on the conditions under which different pesticides might be completely combusted. For example according to the World Bank, WHO, UNEP report, organic pesticides containing mercury should not be incinerated. Organic pesticides must be burned at relatively high temperatures of over 1100 °C, and the gas must be held in the flame for at least two seconds. Organic products containing heavy metals such as tin and lead can only be incinerated in specific cases, under very strict conditions, in dedicated hazardous waste installations equipped with stack gas cleaning devices that can recover these elements (FAO 1996).

The UN FAO states that carbamates, organophosphates and pyrethroids can be incinerated without major limitations in an appropriate incinerator with emission control equipment or in an appropriate cement kiln. Organochlorines and organometals may be restricted depending on the concentration of the active ingredient and the technical specifications of the incinerator and inorganic compounds cannot be incinerated. (FAO 1996).

In a report for the US EPA from 1975 looking into incineration conditions for different types of pesticides concluded that extrapolation of incinerator conditions was difficult and that there was little data available on phosphorous containing pesticides. However, data submitted indicated that these pesticides were successfully destroyed at a temperature range from 620 °C to 1400 °C and retention times ranging from 4 to 12s. The data also suggested that nitrogen containing pesticides require temperatures in excess of 950 °C and retention times of greater than 4s in order to achieve satisfactory cyanide destruction. Halogen-containing pesticides were successfully combusted in different types of equipment under conditions ranging from 2/10 of a second retention time and ~1100 °C temperature to 640 to 700 °C and 8-10s retention time (EPA 1975).

In general, only high temperature hazardous waste incinerators are considered to result in a remarkable percentage of thermal decomposition of pesticides, e.g., incineration of nitrogen containing pesticides under which cyanide compounds will be destroyed are given with >1400 °C. This would only be achieved in HTI incinerators specialised on hazardous waste, but would not necessarily apply to municipal incinerators.

Decomposition of pesticides in question No scientific literature specific to the active ingredients considered in this study were identified.

3.4 Exposure of humans and the environment to emissions from incineration processes According to the HPA report from 2009 the incineration process can result in three potential sources of exposure, (1) emissions to the atmosphere, (2) via solid ash residues, and (3) via

9

HSE 1101 Recycling of home and garden pesticide containers

cooling water. Provided that solid ash residues and cooling water are handled and disposed of appropriately, atmospheric emissions remain the only significant route of exposure to people (HPA 2009).

Greenpeace (internet, accessed July 2012) reports though that ashes have been previously applied to allotments and similar, which can also lead to exposure to toxic incineration products (Greenpeace). However, as bottom ash of incinerated waste mainly consists of inorganic components, the most likely exposure route of humans and the environment to pesticides and their residues when burnt is through gaseous emissions to the atmosphere.

In the HPA briefing note from 2009 it is stated that gaseous emissions from incinerators are generally the source of most public concerns regarding their potential adverse health effects. These emissions are defined in groups and include: Gaseous compounds including hydrocarbons and dioxins Dust (particulate matter PM10, PM2.5 and ultrafine particulates) Metallic compounds Metalloid compounds

It is further stated that incinerator emissions may only pose a potential health hazard if there is a plausible “source-pathway-receptor” linkage. Potential pathways providing a linkage between an incinerator stack (the source) and a local population (the receptors) include: Direct inhalation of stack emissions Deposition to water, then ingestion by humans or animals via water or fish Deposition on farm land or crops and subsequent consumption by humans or animals Deposition to pasture land, ingestion by livestock, then human ingestion Deposition on soil, ingestion of the soil directly or ingestion of crops which have absorbed contaminants from the soil.

Other adverse effects of waste incineration are climate change consequences of emissions (Defra 2007).

3.5 Health and environmental effects from incinerators The comparative impacts on health of different methods of waste disposal have been considered in detail in a report prepared for the Department of Environment, Food and Rural Affairs (Defra 2004). This report concludes that well managed, modern incinerators are likely to have only a very small effect on health. Concerns about possible effects on health of emissions to air tend to focus on a few well known pollutants: particles, polychlorinated dibenzo-pdioxins and polychlorinated dibenzo-p-furans (commonly referred to as “dioxins”) and other carcinogens such as the polycyclic aromatic hydrocarbons (PAH). Both long-term exposure and short-term increases in exposure to particles can damage health. Long term exposure affects the risk of mortality, especially from cardiovascular disease and from lung cancer. Short-term increases in concentrations cause cardio-respiratory effects including an increase in deaths from heart attacks and from respiratory disease, increased hospital admissions for treatment of these disorders and increases in related symptoms. No thresholds of effect can be identified for either the effects of long-term exposure or for the effects of short-term increases in concentrations. Thus, any increase in particle concentrations should be assumed to be associated with some effect on health. The contribution made by waste incineration to national emissions of particles is low. Data provided by Defra show that 2006 national emissions of PM10 from waste incineration are 0.03% of the total compared with 27% and 25% for traffic and industry respectively. The majority (more than 90%) of non-occupational human exposure to dioxins occurs via the diet, with animal-based foodstuffs like meat, fish, eggs, and dairy products being particularly

10

HSE 1101 Recycling of home and garden pesticide containers

important. Limited exposure may also occur via inhalation of air or ingestion of soil depending on circumstances. Regarding emissions from municipal waste incinerators, the current limit for dioxins and furans is 0.1 nanogram per cubic metre of emitted gases. Inhalation is a minor route of exposure and, given that Defra has calculated that incineration of municipal solid waste accounts for less than 1% of UK emissions of dioxins, the contribution of incinerator emissions to direct respiratory exposure of dioxins is a negligible component of the average human intake. However, dioxins may make a larger contribution to human exposure via the food chain, particularly fatty foods. Dioxins from emissions could also be deposited on soil and crops and accumulate in the food chain via animals that graze on the pastures, though dioxins are not generally taken up by plants. Thus the impact of emissions on locally produced foods such as milk and eggs is considered in deciding whether to grant a permit. These calculations show that, even for people consuming a significant proportion of locally produced foodstuffs, the contribution of incinerator emissions to their intake of dioxins is small and well below the tolerable daily intake (TDI) for dioxins recommended by the relevant expert advisory committee, Committee on Toxicity of Chemicals in Food, Consumer (HPA 2009). Certain PAH compounds are known to be potent animal carcinogens and occupational exposure to high levels of PAH has been associated with cancer (EA 1998).

Many studies have investigated how many cancer cases occur close to incinerators. These have mainly considered cancers of the stomach, colorectal, liver, lung, larynx and non- Hodgkins lymphoma. There is no consistent evidence of a link between exposure to emissions from incinerators and an increased rate of cancer. Where apparently significant effects have been observed, these are often in relation to incinerators close to other sources of potentially hazardous emissions, which makes it much harder to pin down the source of any effect. The Government’s independent expert advisory Committee on the Carcinogenicity of Chemicals in Food, Consumer Products and the Environment concluded that “any potential risk of cancer due to residency (for periods in excess of ten years) near to municipal solid waste incinerators was exceedingly low and probably not measurable by the most modern techniques” There is little evidence that emissions from incinerators make respiratory problems worse. In most cases the incinerator contributes only a small proportion to the local level of pollutants (Defra 2004). Studies published in the scientific literature showing health effects in populations living around incinerators have, in general, been conducted around older incinerators with less stringent emission standards and cannot be directly extrapolated with any reliability to modern incinerators. For example, seven studies on cancer incidence near municipal solid waste incinerators which had been published since 2000 and were reviewed by the COC (Comba et al, 2003; Floret et al, 2003; Knox E, 2000; Viel et al, 2000; 2008a and 2008b; Zambon et al, 2007): All had studied the older generation of incinerator and three studies were of an incinerator for which emissions of dioxins were reported to have exceeded even the older emission standard. There were problems interpreting most of these studies due to factors such as failure to control for socio-economic confounding or inclusion of emission sources other than municipal waste incinerators. The COC concluded that “Although the studies indicate some evidence of a positive association between two of the less common cancers i.e. non-Hodgkin’s lymphoma and soft tissue sarcoma and residence near to incinerators in the past, the results cannot be extrapolated to current incinerators, which emit lower amounts of pollutants. Moreover, they are inconsistent with the results of the larger study…carried out by the Small Area Health Statistics Unit.” (COC 2009, HPA 2009).

A main concern of solid residues from incineration is also their re-use as e.g. building materials. Between 1996 and 2000, 79% of these solid residues went to landfill sites, and 21% to ash processors to make into bulk fill (e.g. to construct embankments) or as a substitute aggregate (e.g. in asphalt or construction blocks) (EA 2002). In a study by the EPA from 1996 to 2000, analytical results from all investigated municipal waste incinerators over six months show that concentrations of toxic heavy metals and dioxins are generally

11

HSE 1101 Recycling of home and garden pesticide containers

lower in bottom ash than in air pollution control residues and both are typical of the levels reported in the rest of Europe. Bottom ash, whether at the incinerators themselves or at sites where the ash is either stored recovered or disposed of, does not contribute significantly to the public’s exposure to dioxins. Research into the potential exposure to dioxins in the air of rooms constructed from mixed ash construction blocks indicates these blocks do not release measurable levels of dioxins into the air. Estimates of concentrations of fine dust arising from activities at landfill sites handling air pollution control residues at nearby properties were well within Government recommended air quality objectives (EA 2002).

In theory, APCR and bottom ash should not be mixed, but disposed of separately as hazardous and non-hazardous waste, respectively, to minimise exposure to the more contaminated APCRs. Edmonton has been the only plant reported to mix the two solid residues in the past.

3.6 Gaseous emissions from incinerators The gaseous products formed during the combustion of most organic materials can be classified into two main categories on the basis of their toxicity either as asphyxiant or as irritants with a third category used to describe toxic products not falling within the two main categories.

Asphyxiant gases can give rise to narcosis due to central nervous system depression. Exposure to these combustion products at sufficient concentration, or duration of exposure can lead to unconsciousness and eventually death. The principle asphyxiants produced during combustion of organic materials are carbon monoxide, hydrogen cyanide and carbon dioxide, together with low oxygen concentrations which has similar effects as the asphyxiant gases. These asphyxiants can interact producing additive effects, resulting in higher toxicity.

Sensory irritants affect the eyes and upper respiratory tract (nose, mouth, and throat) and pulmonary irritants affect the lungs. The combustion of most commonly used materials, ranging from natural sources such as wood, to synthetic plastics and polymers, will result in the generation of irritant gases. The most common inorganic acid gases include halogen acids (HCl, HF, HBr) and oxides of sulphur, nitrogen and phosphorus. Other inorganic irritants present in combustion atmospheres include ammonia, chlorine and phosgene. The incomplete combustion of materials will give rise to the formation of organic irritants such as acrolein and formaldehyde.

In many cases the combustion of organic materials (particularly if it is incomplete) may also give rise to more complex molecules which may typically include longer carbon chains and carbon-rings. Some of the compounds considered include polycylic aromatic hydrocarbons (PAHs), dioxins, dibenzofurans, isocyanates, perfluoroisobutylene (PFIB) and particulate matter (PM) (Wakefield 2010).

Dioxins and furans are of particular concern for the public, and emissions of dioxins and furans per tonne of waste from incineration are higher than from other options, with other processes burning waste gases having lower emissions according to Defra (2004). Defra further states that emissions of dioxins from municipal solid waste incinerators can increase levels of dioxins in soil, although the present generation of incinerators release much smaller amounts of dioxins than was the case five or ten years ago. Dioxins from an incinerator in an industrial environment will only slightly increase the total deposition of dioxins. Emissions from municipal solid waste incinerators account for less than 1% of the dioxins experienced by members of the public. Domestic sources such as cooking and burning for heating are the UK’s single largest source of dioxins, accounting for about 18% of emissions. Transport accounts for about 3% and about 4% of the UK total. A number of other sources contribute to emissions of dioxins to a similar or greater extent: accidental vehicle fires; fireworks and bonfires; small-scale waste burning (for example on

12

HSE 1101 Recycling of home and garden pesticide containers

building sites); incineration of other wastes; and the iron and steel industry. Incineration produces the greatest emissions of oxides of nitrogen followed by pyrolysis/gasification and landfill.

Dealing with municipal solid waste results in emissions of about 10,000 tonnes per year of oxides of nitrogen. This is less than 1% of the UK total – the main contributors are electricity. Composting produces the highest emissions of particulates per tonne of municipal solid waste, although incineration is also an important source. Sulphur dioxide emissions are assumed to be similar for all processes which burn waste, or gases generated by decomposing waste Hydrogen chloride and hydrogen fluoride emissions are higher from processes where waste or waste gases are burnt, and incineration is the biggest source of hydrogen chloride. VOC emissions are likely to be greater from landfill, composting and MBT than from combustion processes. Methane emissions, which are important in global warming, are considered to be highest from landfill. Mercury emissions from municipal solid waste incinerators were found to contribute 20% of the overall background mercury concentration at locations surrounding the incinerator. Less than 0.02% of UK emissions of benzene are due to municipal solid waste operations (belonging to the group of PCBs and PAHs). Transport is the main source of benzene, accounting for 47% of UK emissions. Dealing with municipal solid waste accounts for about one tenth of UK emissions of cadmium (Defra 2004).

Generally, emissions from incineration in the UK have changed dramatically, with a 99.8% reduction in emissions since 1990. This was brought about following limits imposed in European Commission directives (Defra 2004).

3.7 Emissions from solid residues A significant amount of research has been carried out on the characteristics and treatment of incinerator residues, the effect of weathering on leaching performance, and the treatment of incinerator residues. A number of researchers are interested in accelerated weathering to predict the long-term leaching behaviour of incinerator bottom ash and APC residues in landfill scenarios. Samples of both bottom ash and fly ash/APC residues were taken from three UK incinerators and subjected to batch and column leach tests and analysis of major and trace components. It was found that the major ion and heavy metal concentrations from samples tested in this scoping study are reasonably representative of bottom ash and APC solid residues and LS 10 leach test compositions previously published in the UK and mainland Europe. Trace organics show greater diversity and significantly higher concentrations in bottom ash than APC residues. In addition, the solvent-extracted organics from the solid residues are dominated by chlorinated aliphatics and aromatics, including trichloroethene, trichloroethane, tetrachloroethane and chlorobenzenes. The corresponding eluates are dominated by aromatic carboxylic acids, ketones, aldehydes, alcohols and esters. Dioxins and furans, although present in significant quantities in the APC solid residues, are not detected in the eluates, even from the 9-11 day column tests. However, some metals were released in significant concentrations; in particular Cd, Sb and Mo. Cu concentrations in bottom ash eluates were also elevated, possibly due to complexation with DOC released from bottom ash samples (EA 2004)

In terms of pesticide incineration, ash and slag produced by high-temperature incineration of pesticides are in principle considered inert. However, to rule out any uncertainties related to the composition of the substance, ash and slag should be disposed of in a lined landfill, unless chemical analysis has established that the substance is fully inert, and that there is no risk that any toxic components might leach out, in which case the landfill does not necessarily need to be lined (WHO 1989).

13

HSE 1101 Recycling of home and garden pesticide containers

References ARC 21; www.arc21.org.uk

Boettner et al. (1973): Combustion products from the incineration of plastics. Report for the USEPA. Braun E. and Levin B. C. (1986): Polyesters: A Review of the Literature on Products of Combustion and Toxicity, Fire and Materials, 10: 107-123.

Braun E. And Levin B.C. (1987) Nylons: a review of the literature on products of combustion and toxicity. Fire and Materials,11: 71-88.

Committee on the Carcinogenicity of Chemicals in Food, Consumer Products and the Environment (2009). Update Statement on the Review of Cancer Incidence Near Municipal Solid Waste Incinerators. Internet: http://www.iacoc.org.uk/statements/documents/COC09S2UpdatestatementonCanNerincidenceandMS WIsMarch09.pdf

Defra (2004): Review of Environmental and Health Effects of : Municipal Solid Waste and Similar Wastes. Internet: http://www.defra.gov.uk/publications/files/pb9052a-health-report- 040325.pdf

Defra (2006): UK voluntary response to WID questionnaire, December 2006. Internet: http://archive.defra.gov.uk/environment/quality/pollution/ppc/envagency/pubs/documents/wid- ukreport.pdf

Defra (2007): Climate Change Consequences Of VOC Emission Controls AEAT/ENV/R/2475. Report to The Department for Environment, Food and Rural Affairs, Welsh Assembly Government, the Scottish Executive and the Department of the Environment for Northern Ireland ED48749102 Issue 3 September 2007

Defra (2007): Incineration of municipal solid waste. Internet: http://archive.defra.gov.uk/environment/waste/residual/newtech/documents/incineration.pdf

Defra; Internet, accessed Jul 2012: http://adlib.everysite.co.uk/adlib/defra/content.aspx?id=000IL3890W.16NTBWTZJ6EU7

Environment Agency (2002). Solid residues from municipal waste incinerators in England and Wales; Internet: http://www.seas.columbia.edu/earth/wtert/sofos/UK-env-agency_incin-residue_2002.pdf

Environment Agency (2002): Solid Residues from Municipal Waste Incinerators in England and Wales. A report on an investigation by the Environment Agency. Internet: http://www.seas.columbia.edu/earth/wtert/sofos/UK-env-agency_incin-residue_2002.pdf

Environment Agency (2004): Testing of residues from incineration of municipal solid waste. Science Report P1-494/SR2. Internet: http://publications.environment-agency.gov.uk/PDF/SCHO0105BIJB-E- E.pdf

Environment Agency (1998): PCB and PAH Releases from Incineration and Power Generation Processes. R&D Technical Report P4-052; Patrick H Dyke. Internet: http://www.pops.int/documents/guidance/nipsfinal/techrep.pdf

EPA (1975): Summation of conditions and investigations for the complete combustion of organic pesticides, EPA 1975, Boyd T. Riley, Jr. Internet: http://nepis.epa.gov/Exe/ZyNET.exe/91013I8F.TXT?ZyActionD=ZyDocument&Client=EPA&Index=Pri or+to+1976&Docs=&Query=&Time=&EndTime=&SearchMethod=1&TocRestrict=n&Toc=&TocEntry= &QField=&QFieldYear=&QFieldMonth=&QFieldDay=&IntQFieldOp=0&ExtQFieldOp=0&XmlQuery=& File=D%3A\zyfiles\Index%20Data\70thru75\Txt\00000018\91013I8F.txt&User=ANONYMOUS&Passw ord=anonymous&SortMethod=h|- &MaximumDocuments=1&FuzzyDegree=0&ImageQuality=r75g8/r75g8/x150y150g16/i425&Display=p

14

HSE 1101 Recycling of home and garden pesticide containers

|f&DefSeekPage=x&SearchBack=ZyActionL&Back=ZyActionS&BackDesc=Results%20page&Maximu mPages=1&ZyEntry=1&SeekPage=x&ZyPURL

FAO (1996): Disposal of bulk quantities of obsolete pesticides in developing countries. Internet: http://www.fao.org/fileadmin/user_upload/obsolete_pesticides/docs/w1604e.pdf

Gödeke, I. (2005): Treatment of pesticides without using incineration technologies. Propose for guidelines, regulations and BAT requirements. Internet: http://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CE8QFjAA&url=http% 3A%2F%2Fwww.greenpeace.org%2Frussia%2FGlobal%2Frussia%2Freport%2F2005%2F6%2Ftreat ment-of-pesticides- withou.doc&ei=7wYkUMm4DIfMhAe60YCIDw&usg=AFQjCNHFbj5JcD9LPRpK9fZUMs5gfXbzSg

Greenpeace; Internet (accessed Jul 2012): http://www.greenpeace.org.uk/MultimediaFiles/Live/FullReport/3809.PDF

Health Protection Scotland (2009): Briefing Note Incineration of Waste and Reported Human Health Effects. Internet: http://www.documents.hps.scot.nhs.uk/environmental/incineration-and- health/briefing-note-incineration-of-waste-and-reported-human-health-effects.pdf HPA (2009): The Impact on Health of Emissions to Air from Municipal Waste Incinerators. Internet; http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1251473372218

Karani, G, Morris, K, Megrahi, MS (2009). Case study to evaluate working environment at Materials Recycling Facility in South Wales, UK. Thesis, Cardiff University. https://repository.cardiffmet.ac.uk/dspace/.../last%20version%204.docm

Kent Enviropower Ltd, Allington (2008): performance report 2008, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Kirklees Huddersfield (2009): performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

LondonWaste Ltd, Edmonton (London) (2008): performance report 2008, Internet: http://ukwin.org.uk/resources/incinerator-reports/

MES Environmental Ltd Wolverhampton (2010) performance report 2010, Internet: http://ukwin.org.uk/resources/incinerator-reports/

MES Environmental Ltd Dudley (2011) performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

MES Environmental Stoke on Trent (2011): performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

MSDS – Deltamethrin, Internet: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=13168#x50

MSDS – Diquat, Internet: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6794#x50

MSDS - ethylene vinyl alcohol - poly(vinyl alcohol-co-ethylene), Internet: http://www.ccp.com.tw/PRODUCT.NSF/0/161de51997f60e05482573b4000870b0/$FILE/MSDS%20E VOH%20EV-3201V.pdf

MSDS - high density polyethylene (HDPE), Internet: http://www.totalpetrochemicals.com/SiteCollectionDocuments/Safety%20Datasheet%20Documents/s ds_us_blackhdpe.pdf

MSDS - Mecoprop-P, Internet: http://www.afpmb.org/sites/default/files/pubs/standardlists/msds/6840- 01-377-7110_msds.pdf; http://www.uap.ca/products/documents/2011-Mecoprop-PPCP27891.pdf

15

HSE 1101 Recycling of home and garden pesticide containers

MSDS – Oxadiazon, Internet: http://www.cdms.net/LDat/mp98K001.pdf

MSDS - polyethylene terephthalate (PET), Internet: http://www.plasticsmadesimple.com/DataSheets/PET_MSDS.pdf; http://www.samhopr.com/product/material/FR530%20NC%28MSDS%29.pdf

MSDS - polyethylene/ethylene vinyl alcohol - poly(vinyl alcohol-co-ethylene), Internet: http://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?country=GB&language=en&produ ctNumber=414093&brand=ALDRICH&PageToGoToURL=http%3A%2F%2Fwww.sigmaaldrich.com% 2Fcatalog%2Fproduct%2Faldrich%2F414093%3Flang%3Den; http://www.polinas.com/grafik/File/msds/evoheng.pdf

MSDS - polyethylene/polyamide, Internet: http://www.shapeways.com/rrstatic/material_docs/msds- strongflex.pdf; http://www.eldonjames.com/pdf/zytel101fnc010.pdf

MSDS – Thiacloprid, Internet: http://www.bayercropscience.com.au/resources/uploads/msds/file7440.pdf

Neath Port Talbpt Ltd Neath Port Talbot (2008) performance report 2008, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Newlincs Development Ltd Grimsby (2008) performance report 2008, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Pyros Environ. Ltd & Tradebe Fawley Ltd Fawley (2009): performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Shetland Heat Energy & Power Ltd Shetland (Lerwick) (2009): performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

SITA Waste Ltd Isle of Man (2009) performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

SITA Waste Ltd Teeside (2009) performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Sovová, K (2008): A study of thermal decomposition and combustion products of disposable polyethylene terephthalate (PET) plastic using the High Resolution Fourier Transform Infrared Spectroscopy, Selected Ion flow Tube Mass Spectrometry and Gas Chromatography Mass Spectrometry. Molecular Physics 106: 1205-1214.

The Coventry & Solihull Waste Disp. Comp. Ltd Coventry (2009) performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Tolvik Consulting (2011): WASTE MARKET WATCH: EfW Operational Performance. Internet: http://www.tolvik.com/markets-and-data/UK-Waste-Market-Watch-EfW-Performance.pdf

Veolia Chineham (2011) performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator- reports/ Veolia ES Hampshire Ltd Marchwood (2011) performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Veolia ES Ltd Portsmouth (2011) performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Veolia ES Ltd Tyseley (Birmingham) (2010): performance report 2010, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Veolia ES Selchp Ltd SELCHP (Lewisham) (2007): performance report 2007, Internet: http://ukwin.org.uk/resources/incinerator-reports/

16

HSE 1101 Recycling of home and garden pesticide containers

Veolia ES Sheffield Ltd Sheffield (2011) performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Veolia ES Southdowns Ltd, Newhaven (2011): performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

Viridor Ltd Bolton (2009): performance report 2009, Internet: http://ukwin.org.uk/resources/incinerator- reports/

Wakefield, J.(2010): A toxicological review of the products of combustion. HPA, HPA-CHaPD-004. Internet: http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1267025520632

WasteNotts Ltd Eastcroft (Nottingham) (2011): performance report 2011, Internet: http://ukwin.org.uk/resources/incinerator-reports/

17