Vet Times The website for the veterinary profession https://www.vettimes.co.uk Keeping tabs on laundry detergent pod toxicity Author : LOTFI EL BAHRI Categories : Vets Date : June 23, 2014 LOTFI EL BAHRI DVM, MSc, PhD considers the potential problems with liquid detergent tablets and their toxic effect on pets, discussing research, risk assessment and clinical signs THERE have been many developments in the formulations of laundry detergents (powder, granule, liquid, and gel), intended to reduce the amount of product required per wash and confer superior cleaning performance. Laundry detergent pods (LDPs), also known as liquid capsules, liquitabs or liquid sachets, have been around since 2001 in Europe and in the US since 2010. Multiple manufacturers sell laundry detergent packaged in pods1-4. These products are formulated by sealing highly concentrated liquid laundry detergent (30ml to 50ml depending on the brand) inside a water-soluble transparent wrapping (polyvinyl alcohol film) intended to be placed directly into the drum of a washing machine. LDPs rapidly dissolve upon contact with water, moisture or saliva2,4,5. Although ingestion of conventional laundry detergent powders by pets usually causes minor symptoms, exposure to the contents of a LDP may result in more severe toxicity, possibly because it’s a highly concentrated product. The LDPs also present special risks due to their very attractive appearance. They are small sized, soft, pleasant smelling, brightly coloured and, as such, might be confused with candy or confectionery. LDPs tend to burst when bitten into, shooting their contents down pets’ throats. Sometimes the concentrated liquid detergent obstructs upper airways or burns eyes or skin. LDPs have become an increasing concern regarding pets and also children. The American Society for the Prevention of Cruelty to Animals (ASPCA) Animal Poison Control Center reported LDPs were second on the list of toxins causing the most reported deaths during 20136. 1 / 8 LDP poisoning is a potentially life-threatening veterinary emergency. Furthermore, the American Association of Poison Control Centers received reports of 10,355 exposures, during 2013, to single- load highly concentrated liquid laundry detergent by children aged five years or younger7,8. Risk assessment LDPs contain complex chemical mixtures, composed of: • anionic surfactants (20 per cent to 35 per cent) – linear alkylbenzene sulfonate (LAS), alcohol ethoxysulfate; • non-ionic surfactants (10 per cent to 20 per cent) – polyoxyethylene glycol alkyl ethers, polyoxypropylene glycol alkyl ethers, and alcohol ethoxylate; • strong alkaline builders; • chelating agents; • enzymes (0.4 per cent to 0.8 per cent) – proteases, amylases; • process aid – propylene glycol (15 per cent to 20 per cent), ethanol, monoethanolamine; and • synthetic fragrance – linalool, eugenol4,8. The toxic dose varies with the ingredients and the concentration of the product. Anionic and non-ionic surfactants have low order of acute toxicity. The oral median lethal dose (LD50) of LAS in rats ranges from 1.080mg/ kg to 1.980mg/kg9. The rat dermal LD50 value is greater than 2.000mg/kg9. Oral LD50 values of non-ionic surfactants is greater than 5g/ kg for rats and dermal LD50 values greater than 2g/kg for rabbits10. Enzymes, used in small amounts, show no acute toxic effects in dogs11. Toxic mechanism LDPs with a pH highly alkaline (10 to 12) are very corrosive12. The order of causticity of alkaline agents (greater to lesser) is: sodium metasilicate > sodium carbonate/sesquicarbonate > trisodium polyphosphates > sodium silicate13,14. LDP products have the potential to cause significant gastrointestinal damage if ingested. Alkaline substances exert a potent solvent action on tissue lipoproteins of cell membranes, producing immediate liquefaction necrosis with intense inflammation13,15,16. In oral exposure, the action of alkalies is immediate. Therefore, gastrointestinal protectants are of limited benefit. The arytenoids, epiglottis and oesophagus are particularly vulnerable to exposure 2 / 8 after ingestion. Rapid onset of mucosal oedema can progress to upper airway blockage and potential lung damage12,16. Ingestion also has potential to result in oesophageal perforation with necrotic extension to the tracheobronchial tree, with potential mediastinitis and death17. Alkaline substances are also potent emetics13,14. Anionic surfactants may induce intravascular hemolysis. Patients with liver disease are particularly susceptible to this13,18. Alkali injuries are potentially the most severe form of chemical eye injury19,20,21. Alkaline agents are toxic to corneal and conjunctival epithelial cells, limbal epithelial stem cells and conjunctival goblet cells22. In addition to alkaline pH, surfactants can elevate intracellular calcium and intracellular acidification, dissipate the mitochondrial membrane potential, decrease the ATP/ADP ratio of corneal epithelia, and induce cell death23,24. LDPs contain irritant ingredients and can produce skin irritations or burns12. Ingestion of propylene glycol in cats may result in severe sedation and lethargy25. Clinical features Exposure to LDPs occur mainly as a result of ingestion. Intoxication by LDPs affects the gastrointestinal tract, as well as pulmonary and CNS. Common clinical signs can occur as early as 20 minutes after ingestion and include18,25,26,27: • profuse vomiting; • ptyalism; • difficulty swallowing; • haematemesis; • abdominal pain; • coughing; • epiglottis oedema; • acute respiratory distress syndrome; and • sudden severe CNS depression. Laboratory results indicate metabolic acidosis with elevated lactate serum concentrations caused by the metabolism of propylene glycol by hepatic alcohol dehydrogenase to lactic acid28,29,30. Death is typically due to the severity of the respiratory signs27. Scarring of the oesophagus or stomach may result in permanent stricture formation and chronic dysphagia30. Following ocular 3 / 8 exposure, which is extremely painful, conjunctivitis and corneal ulcerations are developed31,32. Five cats exposed to spilt concentrated laundry liquid presented severe erosive lesions and extent of hair loss on the limbs. One cat died from the resultant exposure27. Diagnosis The diagnosis of LDP intoxication is based on the history of exposure and rapid onset of significant clinical signs, such as excessive vomiting, difficulty breathing, and profound lethargy. Foaming at the mouth (anionic surfactant) may also suggest exposure. Management In case of ocular exposure, the eyes should be promptly and copiously irrigated with physiologic saline for at least 20 minutes, followed by fluorescein instillation (to check for corneal surface). Bathing and rinsing is recommended for dermal exposures. If LDPs are spilled on clothing, they should be removed. Management of LDP intoxication is listed in Panel 1. It is important to keep LDPs out of the reach of pets. Recently, the largest manufacturer of LDPs added a double-latch lid safety feature to the container in which its pods are sold33. Veterinarians should be aware that LDPs have the potential to cause significant toxicity in pets. References 1. Williams H et al (2012). Exposure to liquid detergent capsules: a study undertaken by the UK National Poisons Information Service, Clin Toxicol (Phila) 50(8): 776-780. 2. Mathew R G, Kennedy K and Corbett M C (2010). Eyes and alkalis. Wave of paediatric eye injuries from liquid detergent capsules, BMJ 340: c1186. 3. Centers for Disease Control and Prevention (2012). Health hazards associated with laundry pod exposures – United States, May-June 2012, MMWR Morb Mortal Wkly Rep 61(41): 825-829. 4. Bonney A G, Mazor S and Goldman R D (2013). Laundry detergent capsules and paediatric poisoning, Can Fam Physician 59(12): 1,295-1,296. 5. Fraser L et al (2012). Liquid detergent capsule ingestion in children: an increasing trend, Arch Dis Child 97(11): 1,007. 6. American Society for the Prevention of Cruelty to Animals Animal Poison Control (2014). Ten top toxins of 2013. 7. American Association of Poison Control Centers (2014). Laundry detergent packets. 8. Williams H et al (2012). Exposure to liquid detergent capsules: a study undertaken by the UK National Poisons Information Service, Clin Toxicol Early Online: 1-5. 9. OECD (2005). Linear alkylbenzene sulfonate, SIDS initial assessment report for 20th SIAM, Paris, France. 4 / 8 10. Material Safety Data Sheet (2001). Non-ionic surfactants, MSDS. 11. Basketter D et al (2012). Enzymes in cleaning products: an overview of toxicological properties and risk assessment/management, Reg Toxicol Pharmacol 64(1): 117-123. 12. McKenzie L B, Ahir N, Stolz U and Nelson N (2010). Household cleaning product- related injuries treated in US emergency departments in 1990- 2006, Pediatrics 126(3): 509-516. 13. Coppock R W, Mostrom M S and Lillie L E (1988). The toxicology of detergents, bleaches, antiseptics and disinfectants in small animals, Vet Hum Toxicol 30(5): 463-473. 14. OECD (2004). Soluble silicates, SIDS initial assessment report for SIAM 18, Paris, France. 15. Calello D and Henretig F (2005). Acids and alkali. In Erickson T B, Ahrens W R, Aks S, Baum C and Ling L (eds), Pediatric Toxicology: Diagnosis and Management of the Poisoned Child, McGraw-Hill, New York: 333-341. 16. Fraser L et al (2012). Liquid detergent capsule ingestion in children: an increasing trend, Arch Dis Child 97(11): 1,007. 17. Safati E et al (1992). Tracheobronchial necrosis after caustic ingestion, J Thorac Cardiovasc Surg 103(3):