1. Egg quality: Chemical residues in respect to food safety E. Esteve-Garcia 1 and J.A. García-Regueiro 2 1 Department of Animal Nutrition, Centre de Mas Bové, Apartat 415, 43280 Reus, Spain 2 Meat Technology Centre, Food Chemistry Unit, Granja Camps i Armet, 17121 Monells, Spain

2. Egg is a very valuable source of nutrients Essential amino acids Vitamins (except vitamin C) and other interesting carotenoids (lutein, zeaxanthin) Essential minerals Linoleic and linolenic acid

3. Monitoring Comission Decission 97/747/EC Directive 96/23/EC Sample should allow tracking Taken at farm level or at packing centre 12 eggs or more 1 sample per 1000 Tonnes of annual production. Minimum 200 samples. 30 % taken at packing centres

4. Monitoring Comission Decission 97/747/EC Directive 96/23/EC Groups tested: 70 % tested for groups A6, B1 and B2(b) –A6 :pharmacologically active substances for which no maximum levels can be fixed (banned) –B1 :antibacterial substances, including sulfonamides and quinolones –B2 (b ) Anticoccidials, including nitroimidazoles 30 % according to situation, but must include B3 (a) –Organochlorine compounds, including PCBs

5. Limits Drugs: MRLs in Unofficial consolidated version of Annexes I to IV of Council Regulation 2377/90. Updated 22/12/2004. Limits for pesticides. Directive 2002/32/CE. Limits for Dioxins. Directive 2001/102/CE.

6. Undesirable (SCAN, 2003) Ions or elements –heavy metals –other trace elements, coming from feeds or water –radionuclides Mycotoxins

7. Undesirable (SCAN, 2003) Other organic contaminants including: – organochlorine compounds pesticides Dioxins –other pesticides –polychlorinated biphenyls –brominated flame retardans –mineral oil hydrocarbons Plant and natural plant products Drugs

8. Heavy metals In general levels are greater in albumin

9. Lead Chronic and cumulative Accidental contamination: –airborne deposition in plants. –Drinking water. Soft waters and leaded pipes. –Paints, Affects enzymes, anemia, renal toxicity, carcinogen, cardiovascular and neurobiological impact Levels are low in eggs (0.003 to 0.259 mg/kg in European surveys) PTWI= 0.020-0.025 mg/kg body weight

10. Mercury Chronic and cumulative Teratogenic and carcinogenic, damages CNS Organic is more toxic. Feeding seed grains treated with methylmercuric chloride to prevent insect infestation. 93 mg/kg in albumen and 5.8 mg/kg in yolk. Accidental contamination in Washington State in 1979 by mercurial fungicides. Nowadays are banned Maximum EU 0.3 mg Hg/kg in calcium carbonate European survey. Avg=0.0013- 0.005 mg/kg. Max= 0.01 mg/kg PTWI= 0.005 mg/kg body weight/week. –< 0.0033 mg/kg body weight/weeek as methyl mercury

11. Cadmium Toxicity: long term exposure Teratogenic and carcinogenic, kidney, bones, neurotoxic Sources: plants grown in Cd rich soils, impurities in minerals, drinking water Present in egg yolk. Transfer is low, retained in follicle walls. Low levels in eggs in surveys (0.001-0.01 mg/kg). PTWI = 0.42 mg/person/week

12. Arsenic Skin lesions and neurological effects Water, arsenicals (discontinued), pesticides As 3 more toxic than As 5 In the egg, yolk/albumen=1/3 At increasing levels in feed a plateau is reached rapidly Low levels in eggs in surveys (0.001-0.006 µg/g). PTWI= 0.015 mg/kg body weight/week

13. Fluorine In phosphate supplements (should be defluorinated). Genotoxic, skeleton (bone fracture), dental fluorosis and hypomineralization of enamel. Transferred to eggshell. High F diets result in 0.4-1.0 mg F/kg fresh albumen, and 3.1-8.4 mg F/kg dry fat free yolk. Risk of bone effects > 5 mg F/day

14. Nitrates Present in water and vegetables Anaemia Nitrites in water. Formation of methaemoglobin Fast excretion in urine. No bioaccumulation. Little information in eggs. Content probably low? Low compared to other sources (water)

15. Limits for feeds (mg/kg) EU (1999-2002) Arsenic2 Lead5 Fluorine350 Mercury0.1 Cadmium0.5

16. Radionuclides Transfer is higher than for other animal products Experience from Chernobyl accident: 137 Cs and 131 I from contaminated cereals. Countermeasures: Iron (III) hexacyanoferrates U and Po in phosphates in Israel. Dose equivalent for all poultry products (70% of meat) is 0.04 mSv/year. (According to ICRP individual doses of less than 10 μSv/year are negligible) Limits according to Council Regulation (EURATOM) No 2218/89 (Bq/kg) – 90 Sr: 125; 131 I: 500; 239 Pu and 241 Am: 20; 134 Cs and 137 Cs and all t 1/2 > 10 days: 1000 – 3 H, 14 C and 40 K are excluded

17. Mycotoxins Eggs < animal feeds. Unlikely acute toxicity Aflatoxin B1, M, ochratoxin A are carcinogenic and must be monitored. Fumonisin, Vomitoxin, and zearalenone found at very low levels or not found ata all when contaminated feeds are given to hens.

18. Ochratoxin A No information in eggs of laying hens In Japanese quail there is transfer to eggs. Contribution of products of animal origin is not more than 3 % of the burden

19. Aflatoxin B1 Residues when feed is 500 µg B1/kg feed but not at 300 µg B1/kg feed Transfer 4615:1 in yolk, 3846:1 in albumen In Japanese quail transfer is higher After 7 days withdrawal only traces in eggs Limit in feeds is 0.02 mg B1/kg feed Limit in eggs is 3 pg WHO-PCDD/F-TEQ/ g fat Maximum level based on ALARA

20. T2 Toxin Inmunosupresive and carcinogenic 1 mg T2 for 8 days 0.9 µgT2/egg Limits in Israel and Russia: 0.1 mg T2/kg feed

21. Organochlorine pesticides Transferred to eggs in many cases Very persistent. DDT (metabolites) still can be found in eggs more than 25 years after use was discontinued. Banned for most applications in Europe and USA but still used in some third world countries: Monitoring of eggs and feed ingredients Limits for complete feeds and supplemental fats: see manuscript, adapted from EU 1999

22. Brominated flame retardants Accumulated like PCBs. From landfill and industry emissions Transferred to eggs Weight loss, liver damage, inmunity and reproduction. Carcinogenic Banned in Europe. Survey in Catalonia (Spain) PBDEs 58.3-64.5 ng/kg of wet weight in eggs NOAEL is 0.15 mg/kg BW (WHO, 1994)

23. Plant and natural plant products EU list of 1999 includes 17 plant species and 5 natural products According to SCAN risk is low. Affect health of animals rather than the products derived from them

24. Mineral oil hydrocarbons Carcinogen Accidental contamination of fats and oils from gas oils (C18-C35) or synthetic oils (C25 and beyond C45) by discharge of waste oils. FDA maximum in cereals is 100 mg/kg Survey in Switzerland in fats for animal feeds levels between 100 and 1000 mg/kg. –In 1999 in the fat phase of eggs average 30 mg/kg, and maximum 80 mg/kg.

25. Prevention At farm level: –Good production practices. Control and traceability of feeds Wtihdrawal time for drugs Control of drinking water Feed –Monitoring of ingredients. European legislation HACCP Traceability

26. Eggs are very valuable sources of nutrients Knowledge of risks is necessary to prevent contamination