The Effect of Environmental Hazards on the Health of the Young Dr

THE EFFECT OF ENVIRONMENTAL HAZARDS ON THE HEALTH OF THE YOUNG DR. A. MUSCAT BARON DEPARTMENT OF PAEDIATRICS, ST. LUKE'S HOSPITAL DR. Y. MUSCAT BARON DEPARTMENT OF OBSTETRICS AND GYNAECOLOGY, ST. LUKE'S HOSPITAL

'If you go to American city, You may find it very pretty, Just one thing that you must beware, Don't drink the water and don't breathe the air' T. Lehrer in 'Pollution '1

The environment refers to the ment of a child but also hazard­ factors. The incidence of child­ medium in which we exist. Our ous in many ways. Some of these hood obesity in the U.S. in­ health depends on the ongoing noxious effects of the environ­ creases especially among chil­ events taking place in our sur­ ment, their effects on the foetus dren of elementary and high roundings. The environment can during pregnancy and on infants school age. This problem is also have direct or indirect hazard­ and children will be described markedly on the increase in the ous effects on our health. Sev­ below. UK4 and in other Western coun­ eral noxious effects can reach tries, where about 10-15% of us through ingestion, inhalation, Poverty is a major culprit be­ preschool children are consid­ and througl;l contact with our hind many problems that will be ered to be overweight. 5 Some of skin. These hazards may also described. Poor nutrition during the factors thought to increase affect the unborn child, evading pregnancy is harmful to the un­ the risk of childhood obesity are the protective and nurturing born child since its growth de­ environmental factors indirectly body of its mother. pends entirely on the maternal exerting their effect on children food supply. Lack of proper nu­ such as having obese parents, The environment is relatively trition may result in intrauterine being an only child and leading more hazardous to infants and growth retardation. The propor­ a 'sedentary life' by spending children because they are struc­ tion of low birthweight babies long hours watching TV instead turally and functionally different (usually taken as less than the of engaging in physical exer­ from adults. Children have a 10th centile for gestational age) cise.6 larger surface area to body reflects the health and nutritional weight ratio. Their higher meta­ status of the mother. 2 Poverty is Childhood obesity has also bolic rate requires more oxygen also the cause of widespread been noted as a serious national intake. They grow at a faster malnutrition affecting children problem in the Maltese Islands rate, especially during the first across the world. Malnutrition in the mid-1990's, increasingly six months of their life. Some makes children more prone to affecting older children (around body organs are functionally im­ infection. Infection in turn, fur­ 10 years of age), females more mature at birth and organ matu­ ther exacerbates malnutrition than males.7 Moreover, the inci­ rity progresses at different rates. resulting in a vicious cycle. Both dence of overweight babies in Children also need more energy malnutrition and infection are Malta, with about 12% of the and fluids per unit body weight attenuated by breastfeeding. newborn baby population weigh­ compared to adults. Thus, the However, breast-feeding is not ing 4 kgs and over, is higher greater requirement of fluids, completely risk-free. Most fat­ than that of many other coun­ food and air makes them more soluble chemicals ingested by tries.s vulnerable to environmental haz­ the mother can be transferred to ards.2,3 the child via breast-milk. Lead poisoning can occur through ingestion of contami­ Children require access to Obesity on the other hand, is nated food or water and also by clean water, clean air and pro­ the most common nutritional inhalation of lead-polluted air. tection from polluting toxic sub­ problem of children in many Central nervous system prob­ stances in order to sustain nor­ parts of the developed world, lems such as convulsions, be­ mal growth and development. 1 especially the United States, and havioural changes, mental re­ The environment can be instru­ is caused mainly by inappropri­ tardation, irritability, lack of co­ mental in assisting the develop- ate environmental habits and ordination and clumsiness may

DECEMBER 1998 2 it-tabib tal-Jamilja occur in children and may per­ tubular dysfunction and bone heavy traffic. Another significant sist into adulthood.2 defects. Such medical compli­ source of CO to the foetus is cations arose in Japan after the cigarette smoking (passive or Women working in lead-us­ ingestion of rice grown in pad­ active) by the pregnant mother. 14 ing trades were found to have dies, irrigated with cadmium­ This gas diffuses easily through unusually high rates of infertil­ contaminated river water. 2 the placental tissues, producing ity, spontaneous abortion, still­ a concentration of 10 to 15 per­ birth and neonatal death. This In cases of methylmercury cent higher in the foetus than in observation in many parts of poisoning following ingestion of the mother. This jeopardises foe­ Europe, led to the banning of seafood in Japan, and dressed tal oxygen availability leading such trades for women.9 Chil­ seed in Iraq, many infants were to retarded growth, brain dam­ dren, especially at an early age, born with microcephaly, irrita­ age or death. 12 « 6 years) may ingest lead bility, cerebral palsy, or later through contaminated soil, dust developed epilepsy.9 Cigarette Smoking and En­ and also by eating leaded paint vironmental Tobacco Smoke chips.10 Eating food sold by The environment can also be (ETS): This form of indoor pol­ street vendors, after being ex­ hazardous through deficiencies lutant produces intrauterine posed to road dust containing of certain essential trace ele­ growth retardation and increases high levels of lead is yet another ments. Trace element deficiency the risk of spontaneous abor­ source.2 'Clean' foods such as - Severe Zinc deficiency in child­ tions, premature deliveries and canned fruits, vegetables and hood is associated with dwarf­ perinatal deaths.9,14 An interest­ fruit juices have been found to ism and hypogonadism and this ing finding is that children born be the biggest contributors of has been found especially com­ to mothers who smoked during lead in a child's diet.9 monly in the Middle East. In pregnancy were on average 1- 2 neonates, this can cause acro­ cm shorter, compared to other Drinking water coming from dermatitis enteropathica. Infants children, after accounting for lead-lined water tanks or from born to mothers with Iodine de­ several confounding vari ­ copper piping joined by lead ficiency during pregnancy have ables. 9, 14, 15 The intellectual abil­ solder, used in modern water a greater risk of both motor and ity and behaviour of these chil­ systems forms another source.2 mental retardation. Iron defi­ dren may be affected.9,16,17 There Adding lime, or in some areas, ciency causes anaemia, which has also been some speculation orthophosphate, has helped in in infants has been shown to of increased risk of childhood preventing lead dissolving in the decrease intellectual ability. cancers in children exposed to water-pipes. 11 Lack of Fluoride in children is smoking during pregnancy but associated with dental caries.9 further studies are still required Automobile traffic emits ex­ in this area.9,14 haust gases containing predomi­ Another source of environ­ nantly inorganic lead aerosol. mental hazard is through pesti­ Cigarette smoking and ETS Use of lead-free gasoline, read­ cides such as DDT and its de­ have been known to cause res­ ily available in some countries, rivatives which pass through the piratory problems for a long time. has produced cleaner air. Re­ placenta and affect the fetus. Children are especially at risk of moval of lead from gasoline Reproduction is affected and developing asthma through ETS started in USA in 1972 and was birth defects and cancer have from their parents, mostly from completed in 1995. This prac­ been demonstrated in animal their mother. 14, 18, 19,20 Some stud­ tice has resulted in almost four­ research.2 ies 20,21,22 have shown that lung fold reductions in the median function diminishes in children blood lead level of high risk chil­ Accidentally ingested poly­ exposed to ETS. A higher inci­ dren (6 months to 5 year olds) in chlorinated biphenyls (PCBs) dence of otitis media, rhinitis, Chicago. 12 ,13 However, the op­ slow fetal growth and later im­ atopy and resorting to tonsillec­ posite is happening in develop­ pair neural development. Eat­ tomy has been associated with ing countries where increase in ing rice-oil contaminated with passive smoking (ETS) .14 ,20 Ex­ traffic and unrestricted use of PCBs led to a number of Japa­ posure to ETS is also thought to leaded petrol occurs in urban nese women giving birth to af­ be a risk factor for Sudden Infant cities. fected children. PCBs can also Death Syndrome (SIDS).2,14 A be excreted in breast milk.9 relationship has also been found Cadmium is a heavy metal between ETS and the develop­ which enters the body through Inhalation of hazardous com­ ment of purulent meningitis in the same sources as lead and pounds adds to the list of envi­ children.23 ,24 Exposure of chil­ also through smoking (active or ronmental dangers. High levels dren to ETS has shown an in­ passive). Long-term exposure of Carbon Monoxide (CO) are creased risk of leukaemia and to cadmium can lead to renal found in urban cities loaded with lymphoma during adulthood.20

D ECEMB ER 1998 3 it-tabib tal-familja Passive smoking (ETS) also pre­ twice as many stillbirths as when Poor drainage of stagnant wa­ disposes children to increased alcohol is consumed alone.2 ters and badly planned irriga­ lower respiratory tract illness Children of alcoholic mothers tion systems encourage mos­ rates, especially in the first year are more likely to have behav­ quito infestation, many of which of life. 20,25 iour problems and low IQs.9 may carry malaria.2 Malaria is endemic in 102 countries, plac­ Research has also shown that Loud noise is yet another ad­ ing over halfthe world's popula­ the physical distance between a verse effect of the environment, tion at risk. Other water-borne baby and the nursing mother and which can lead to defective parasitic infections such as who smokes and the amount of hearing. Pregnant mothers ex­ schistosomiasis, transmitted by cigarettes smoked correlates posed to a lot of noise at work snails, is hazardous to the older with the amount of Cotinine gave birth to children who age-group (10-14 years) who (used as a marker) found in the showed an increased risk of place themselves at risk by bath­ ing and washing in infested ca­ baby's urine. These mothers hearing loss.9 2 were not exposed to ETS but nal water. were smokers themselves, Food additives and preserva­ HIV infection - AIDS poses smoking either away from the tives can be harmful to our baby or during breastfeeding. another 'environmental' threat health. Tartrazine (E 102) is an to the growing foetus. Babies Babies of mothers who smoked additive commonly used in the while nursing were found to have born to infected women have form of an orange-yellow col­ 25-40 percent chance of being even higher levels of cotinine in ouring, in both foods and drugs. the urine. 26 infected before or after birth. E102 has been implicated in The infected children are almost causing adverse reactions such all destined to die by the age of Smoking among the children as bronchospasm, urticaria and 5 years.2 The few that survive themselves is a growing epi­ 29 angioedema. are soon orphaned after their demic. Regular smoking at 10 - infected parents pass away. HIV 15 years of age is becoming as Infants are more vulnerable infection can also be transmit­ increasingly common practice to waterborne chemicals and ted through breastmilk.30 (among girls more than boys), infections than older children especially in places like Italy, because of a larger water intake Air pollution has become a France and Germany where in relation to their body weight. major global problem affecting more than 30% are regular smok­ Ground-water, and more so, mostly children in more local­ ers at this age. Moreover, smok­ well -water, can contain nitrates, ised areas such as urban cities. ing tends to be associated with especially in countries where use Young children inhale twice as illicit drug use among these of nitrate fertilisers and manure many air pollutants than do young people.27 in agriculture has increased. adults since more air is inhaled Bacteria in the GIT convert ni­ per unit body weight.!! The ef­ Yet another hazard emerging trates to nitrite and this induces fects of cigarette smoking and from the environment is illicit methaemoglobinaemia, espe­ ETS on children have already drug addiction. Cannabis is cia

y in infants. Another source been discussed above. widely consumed, besides other is vegetables. WHO has recom­ drugs like amphetamines, bar­ mended that infant formula milk Another form of indoor air 2 biturates and tranquillizers. should be prepared using low­ pollution is through gas cook­ Drug abuse during pregnancy nitrate water (at least <45mg/ ing. Gas used for cooking, heat­ gives rise to premature deliver­ L). Nitrates can react with ing water or space heating is ies. Low birthweight, smaller amines to form nitrosamines, again quite hazardous to health, head circumference as well as which are potent carcinogens in especially pregnant women who SIDS were associated with opi­ animals. Such compounds are might be spending more time in 9 ate addiction. used in the manufacture of baby the kitchen or in front of the 2 pacifiers. fireplace. Nitrogen dioxide and In 1973, Jones et al showed nitric oxide emitted during cook­ that excessive consumption of Lack of safe, clean water and ing using oil stoves, gas-fired alcohol during pregnancy can sanitation services can lead to appliances and open fires leads lead to a variety of congenital repeated attacks of infective di­ to increased susceptibility to malformations and low arrhoea in infants and children. both bacterial and viral respira­ birthweight - the 'foetal alcohol In underdeveloped countries, tory infections and impaired lung syndrome'.28 The combined ef­ this leads to malnutrition, stunt­ function.3!,32 In Moscow, the fect of alcohol and smoking by a ing of physical and mental prevalence of childhood asthma pregnant mother further aggra­ growth and a substantial number was much higher in areas with vates the situation and leads to of deaths from dehydration.2 high concentration of nitric ox-

D ECEMB ER 1998 4 it-tabib tal-Jamilja ide and other pollutants.33 Simi­ Toxic waste (eg. cyanide kaemia cluster (the Kinlen Hy­ lar health effects occur with waste) dumped illegally may end pothesis).37 smoke and S02 pollution from up in places such as play­ coal consumption and industrial grounds. Beaches polluted with Another type of radiation is plants in developed countries. 11 sewage contain coliform bacte­ electromagnetic radiation found The noxious effects of gas cook­ ria which can cause infection of wherever there is electric power. ing was investigated in the Mid­ the gastrointestinal tract, ear, An increased risk of all cancers dle East among children of Ku­ nose and throat, eyes and skin.11 in children has been associated waitis and of Europeans living [n 1957, a 6 year old girl devel­ with the use of electric blankets. there. The lung function was sig­ oped polio and subsequently The use of electric appliances nificantly impaired in fami­ died after having bathed near a has been associated with pre­ lies using gas for cooking. sewage outflow in the Solent, mature labour.9 Moreover their children were UK. Such a risk is diminished approximately 3cm shorter than nowadays with increasing im­ Children are adventurous and children having electric cookers munisation coverage. therefore more likely to be in­ at home.34 jured by falls, drowning, scald­ Ionising radiation can also ing, burns and accidental inges­ Wood-burning fireplaces pro­ have hazardous effects on one's tion of dangerous liquids and duce several pollutants which health. This form of radiation drugs. Such incidents are also may include cancer-causing mainly affects the process of products of the environment. agents such as benzo-a-pyrene cell division. Brain damage in Accidents are more common in and other gaseous pollutants the foetus may occur especially places where children live in such as CO and formaldehyde. if the pregnant mother is ex­ poverty, poor housing and where The famous London smog of posed to radiation during the social isolation of lone mothers 38 1952 lead to over 4000 deaths first trimester. 2 Many children exists. affecting mostly children under born after the atomic bomb at­ the age of one. The disaster lead tacks in Hiroshima and Naga­ The environment is also a to the Clean Air Act (1956) and saki suffered severe mental re­ means of educating society. an end to coal fires in the UK .9,11 tardation. Studies2,9 have indi­ However, education is not avail­ cated that children born to moth­ able to all societies alike. [n de­ Ozone is a dangerous irritant ers irradiated during pregnancy, veloping countries, around to eyes, throat and lungs.9 Stud­ are more likely to die of cancers, 50% of children attend primary 2 ies9,35 carried out during periods but further research is required school. However, only about of high ozone pollution has in this area. 20% of boys and 10% of girls shown a baseline shift of pulmo­ attend secondary school. These nary function in children and an The natural level of radioac­ percentages vary in different increased number of hospital tivity is increased by human countries. More girls tend to be visits for asthma. activity such as medicine, nu­ kept at home in order to do clear fallout from weapon test­ chores such as fetching wood ing and industrial and nuclear and water in these developing Streets, playgrounds and plants using radioactive by­ countries. This later reflects it­ beaches can also be hazardous products.1 1 Radiation affects self in the lack of knowledge to children's health. Junk foods cell-division mostly of blood­ about hygiene and health in sold to young children are occa­ forming tissues, sex-glands and these girls who later bear their sionally contaminated, some skin. Leukaemia clusters of chil­ own children. This sex discrimi­ contain unlicensed colouring dren living close to nuclear nation also extends further in agents and additives and others plants, have been cause for some parts of Asia and Africa, are uncooked and/ or unwashed.2 much conc ern. Such a cluster with girls being given second occurred in a village close to a rate health care and nutrition. 2 Children may be exposed to nuclear plant in Sellafield, UK in Lack of education results in lack dog-fouling on playgrounds. In the early 1980s, initiating much of knowledge about the environ­ the UK , about 100 people a year, research into the matter. How­ ment. This in turn, leads to inad­ mostly children, become partly ever, leukaemia clusters have equate use of facilities that the or totally blind as a result of also been found in areas where environment provides, with re­ ingesting the eggs of a parasite power plants have been planned sulting malnutrition, ill health, (toxocara canis) found in dog but never built. This might be illiteracy, poverty, crime and faeces. Another type of toxocara explained by population migra­ war. causes wheezing and skin tion to this area leading to epi­ rashes. Salmonella bacteria has demics of common viral infec­ Child labour is a preferred also been known to contami­ tions in the new towns. 9, 11 ,36 This 11 option to education in some nate playgrounds. in turn may contribute to a leu- countries. Poverty drives chil-

DECEMBER 1998 5 it-tabib tal-familja dren to go to work at a very deforestration and deser­ 4. Spencer N. Poverty and tender age, partly to help their tification just to name a few. Child Health. Oxford : family income, and partly to help Global warming and ozone de­ Radcliffe Medical Press, themselves especially ifthey are pletion are expected to change 1996;98-129. homeless. Some children work disease patterns as well as per­ for long hours without proper haps decreasing our immune 5. Polnay L, Hull D. Commu­ rest and nutrition and are con­ response to various infections.2 nity Paediatrics. Edinburgh: tinuously exposed to risk espe­ Children, again, are the most Churchill Livingstone , cially in certain lines of work vulnerable sector of our popula­ 1993;386-417. (toxic vapours, corrosive liquids, tion, and tend to be affected the and a whole range of infections most by these problems. 6 . Kaplan DW , Mammel KA . in garbage collecting). Ninety­ Adolescence. In: Hathaway eight percent of economically The United Nations Conven­ WE, Hay WW , Groothuis JR, active children are in fact, found tion on the Rights of the Child. Paisley JW eds. Cur­ in developing countries.2 Article 24 specifically deals with r ent Pediatric DiagnOSiS environment stating that 'chil­ a nd Tr eatment. Con­ Poverty also drives children dren have the right to li ve in a n ecticut : Appleton and homeless; on the street with no safe, healthy and unpolluted Lange, 1993:85-138. roof over their head, begging, environment with good food and stealing, doing odd jobs like shoe clean, drinking water'. Heads of 7. Department of Health, Malta. shining and washing cars. Some State are continuously labour­ Promoting healthy eating of these children form gangs, or ing towards reaching this goal; habits in Malta : A situation enter the drug trade or prostitu­ for some countries, this will analysis and proposals for tion. The World Health Report in obviously take longer than action. 1992: 1.14. 1995 states that extreme pov­ others.41 erty is 'the world's biggest killer 8. Muscat Baron Y, Muscat and the greatest cause of ill­ Mankind is permanently un­ Baron A, Brincat M. Risk fac­ health and suffering across the der the reign of the environment. tors preceding shoulder dys­ globe'.39 We, as part of society, should tocia in labour. Arch Obstet treat our environment with care Gynaecol 1996;V:3-9. Unfortunately, children are and reverence and make sure also victims of war. About 2 that we do not underestimate its 9. Golding J. The environment million children are estimated to influence on our health. When­ and child health. In: Harvey have been killed in wars during ever we can, we should strive to 0, Miles M, Smyth D. eds. the past decade. Child soldiers try and make it better, espe­ Community Child Health under the age of 16 years, num­ cially for the sake of our voice­ and Paediatrics. Oxford: bered as many as 200,000 in less population, the children of Butterworth Heinemann , 1988 alone. Land-mines pro­ the world. 1995:263-277. vide the most lethal weapon of all, especially to children play­ Acknowledgements 10.McElvaine MD, DeUngria ing or working in fields. About EG, Matte TO et al. Preva­ 110 million land-mines still re­ The authors wish to acknowl­ lence of radiographic evi­ main unexploded in 64 coun­ edge the useful advice given by dence of paint chip ingestion tries around the world.40 Wars Or. S. Attard-Montalto, Chair­ among children with moder­ do not just kill children but many man, Department of Paediatrics. ate to severe lead poisoning. are disabled, left homelsss, or­ Pediatrics 1992;89:740-2. phaned and many more are psy­ REFERENCES chologically traumatised, prob­ 11 . Children's Legal Centre. The ably for life. 1. Polnay L, Hull D. Commu­ framework of environmental nity Paediatrics. Edinburgh: law. Childright 1989; 12-16. CONCLUSION Churchill Livingstone, 1993:246. 12. Hayes EB, McElvaine MD, The state of our environment Orbach HG et al. Long-term affects the health of all strata of 2. Environmental quality and trends in blood lead levels society, especially that of in­ children - today and tomor­ among children in Chicago : fants and children. Besides the row. UNICEF. 1992;2: 17 -45. relationship to air-lead lev­ problems mentioned above, els. Pediatrics 1994;93: 195- more ominous hazards with far­ 3. Bearer CF. Environmental 200. reaching consequences loom on health hazards : how chil­ the horizon. These include glo­ dren are different from adults. 13. Silbergeld EK. Preventing bal warming, ozone depletion, Future Child. 1995;5: 11 -26. lead poisoning in children.

DEC EMBER 1998 6 it-tabib tal-familja Annu Rev Public Health passive smoking and puru­ bient air pollution. Sci Total 1997;18:187-210. lent meningitis. Chung Hua Environ 1994;148:57-60. Liu Hsing Ping Hsueh Tsa 14. Charlton A. Children and Chih 1994;15:107-9. 34. Jedrychowski W, Khogali M, passive smoking: a review. Elkarin MA. Height and lung J Fam Pract 1994;38:267- 24. Bredfelct RC, Cain SR, function in preadolescent 277. Schetze GE et al. Relation­ children ofKuwaitis and Eu­ ship between passive to­ ropean origin: a pilot study 15. Berkey CS, Ware JM, Speizer bacco smoke exposure and of health effects of gas cook­ FE et al. Passive smoking the development of bacterial ing in the Middle East. and height growth of meningitis. J Am Board Fan Arch Environ Health preadolescent children. lnt J Pract 1995;8:95-8. 1991 ;46:361-5. Epidemiol 1984; 13:454-8. 25. Jedrychowski W, Flak E. 35. White MC, Etzel RA, Wilcox 16. Bauman KE, Flewellin RL, Maternal smoking during WD et al. Exacerbation of La Prelle J. Parental ciga­ pregnancy and postnatal childhood asthma and ozone rette smoking and cognitive exposure to ETS as predis­ pollution in Atlanta. Environ performance of children. posing factors to acute Res 1994;65:56-68. Health Psychol 1991; respiratory infections. 10:282-8. Environ Health Perspect 36. Stiller CA, Boyle PJ. Effect of 1997; 1 05(3) :302-6. population mixing and so­ 17. Weitzman M, Gortmaker S, cioeconomic status in Eng­ Sobol A. Maternal smoking 26. Charlton A. Children and land and Wales, 1979-85, and behavioural problems passive smoking: a review. on lymphoblastic leuk­ in children. Pediatrics J Fam Pract 1994;38:267- emia in children. BMJ 1992;90:342-9. 277. 1996;313: 1297 -1300.

18. Soyseth V, Kongerud J, Boe 27. Holland WW, Fitzsimons B. 37. Kinlen LJ, Clarke K, Hudson J. Postnatal maternal smok­ Smoking in children. Anno­ C. Evidence from population ing increases the prevalence tation. Arch Dis Child mixing in British new towns of asthma but not of bron­ 1991 ;66: 1269-1274. 1946-85 of an infective basis chial hyperresponsiveness or for childhood leukaemia. atopy in their children. Chest 28.Jones KL, Smith DW, Lancet 1990;336:577 -82. 1995; 107:389-94. Ulleland CN et al. Pattern of malformation in offspring of 38. Roberts I. Pless B. Social 19. Ogston SA, Du V Florey C, chronic alcoholic mothers. policy as a cause of child­ Walker CHM. The Tayside in­ Lancet 1973;1 :1267-71. hood accidents: the children fant morbidity and mortality of lone mothers. BMJ study : effect of health of us­ 29. Pollock I. Food additives. 1995;311 :925-8. ing gas for cooking. BMJ In: David T J ed. Recent Ad­ 1985;270:957 -960. vances in Paediatrics 10. 39. The state of the world health. Edinburgh: Churchill World Health Report 1995 - 20. Etzel RA. Active and passive Livingstone, 1992: 129-144. executive summary. smoking: hazards for chil­ dren. Cent Eur J Public 30. Johnstone FD. HIV and preg­ 40. Bellamy C. The State of the Health 1997;5(2):54-6. nancy. Br J Obstet Gynaecol World's Children 1996. 1996;103:1 184-1190. UNICEF Oxford University 21.Cook DG, Whincup PH , Press, Oxford. Papacosta 0 et al. Relation 31. Anonymous. Oxides ofnitro­ of passive smoking as as­ gen and health. Editorial. 41. United Nations Convention sessed by salivary cotinine Lancet 1981;1 :81-2. on the Rights of the Child. concentration and question­ HMSO Publication, Londbn. naire to spirometric indices 32. Melia RJW, Du V Florey C, in children. Thorax Altman DG et al. Associa­ 1993;48: 114-20. tion between gas cooking and respiratory disease in 22. Smoking and the young. children. BMJ 1977;2: 149- Royal College of Physicians 152. 1992. London, UK. 33. Revich BA. Child health level 23. Wang L, Cheng M. Childhood in Moscow as related to am-

DECEMBER 1998 7 it-tabib tal-familja