Ammonia emissions: Poultry and human welfare issues

1. Ammonia emissions: Poultry and human welfare issues Inma Estevez, Ph.D. Department of Animal and Avian Sciences, University of Maryland, College Park, USA Bud Malone Department of Animal & Food Sciences University of Delaware Georgetown, DE

2. Complex dynamic system of Physical and biological factors Physiological and behavioral factors, management system, light, temperature, humidity, ventilation + Density • Organic & inorganic dust • Pathogens & other micro- organisms • Gases such as: Carbon monoxide, methane and AMMONIA

3. What is ammonia? • Ammonia: is a colorless, highly irritant, alkaline gas which is generated by microbial activity on faecal uric acid when the litter is moist. • Properties of Ammonia: • It is a water soluble gas and can thus be absorbed in dust particles and litter as well as mucus membranes. • It is toxic to animal cells. The known symptoms of ammonia poisoning include: conjunctivitis, coughing, sneezing and dyspnoea.

4. Factors affecting ammonia production Relative humidity Water spillage Poor ventilation Poor litter management Litter PH Health status Diet composition Density Litter depth, composition and PH Manure production House floor High litter moisture High ammonia

5. Welfare considerations • Ammonia emissions in broiler houses are a welfare concern because it may produce a serious threat to the health of the birds such as; increase risk of skin burns.

6. Welfare considerations • Effects of NH3 on the “five freedoms” : Freedom from NH3 effects 1- Hunger, thirst and malnutrition Reduce feed intake and cause weight loss 2- Disconfort Irritation of membranes which may cause discomfort 3- Pain Cause health problems that are likely to be painful 4- Normal behavior Hens show preference for fresh air than ammoniated atmospheres 5- Fear and distress No evidences- should be investigated (From Kristensen & Wathes, World Poultry Science, 2000)

7. Effects on birds’ health • Main health & welfare effects associated with high ammonia levels include: • High incidence of contact dermatitis: foot, hock and breast burns that can be a gateway for bacteria causing further health problems to the birds. • Trachea & Lung lesions which are associated with fluid accumulation and low blood oxygen, rendering the birds more susceptible to bacterial infections such as E. coli (Oyetunde et al., 1978). • Eye irritation.

8. Effects on birds’ health • Effect of rearing conditions on the prevalence of foot- pad dermatitis at slaughter (% of flocks): (Ekstrand et al., 1997).

9. Effects on birds’ health • Other less prevalent problems include: • Ascites (Lopez coello et al., 1985; Anthony et al., 1994). Terzich et al., (1998) found that the occurrence of ascites was directly correlated to ammonia levels. • Gastrointestinal irritation (Pickrell, 1991). • Lameness consequence of foot-pad dermatitis (Greene et al., 1985)

10. Effects on Performance Ammonia levels and consequences: • 10 ppm: Trachea irritation (in turkeys). • 20 ppm: Increase rate of infection of Newcastle disease vaccination. • 25 ppm: Impaired growth rate and feed conversion. Reduced final body weight. • 25 ppm- 50 ppm: Air sac inflamation • 50 ppm: Increased levels of keratoconjunctivitis. • 100 ppm: Increased chick mortality - +

11. Other considerations • Some of the above mentioned pathologies are know to be painful for the birds. • The frequency and severity of the lesions are highly dependent on the exposure time, therefore they are likely to increase with age of the birds. • Birds at high densities may be more susceptible to contact dermatitis due poorer plumage condition, and usually show a higher incidence and severity of hock and breast lesions. • Acute outbreaks of litter deterioration are responsible of the highest incidence of contact dermatitis, which most commonly is observed between 4 and 5 weeks of age. Sudden loss of litter friability due to saturation may be the cause.

12. Effects on breeders • Consequences of high NH3 in broiler breeder flocks: • There is very little research on the impact of levels of NH3 on the performance of broiler breeders. However foot-pad dermatitis is suspected to interfere with mating efficiency. • Preliminary results of ongoing investigations on factors affecting fertility in broiler breeders indicate that foot problems infections can reduce by approximately 50% the fertility of broiler breeders (Estevez, 2001).

13. Effects on breeders Feed restriction Over drinking Wet litter + Male Fertility - NH3 Staphilococus infections Long term housing Poor management - Female Fertility Foot problems

14. Minimum standards for poultry EU Legislation NH3 ppm Source Sweden 25 Ekstrand, 1993 Recommendation of the European Union, (2000): • Not to exceed 20 ppm NH3 (based on; Wathes, 1998. World Poultry Science Journal, 54:544-550). (http://europa.eu.int/comm/food/fs/sc/scah/out39_en.pdf)

15. Minimum standards for poultry Recommendation NH3 ppm * American Humane Association 10 recom.- 25 max. * McDonalds 25 * National Chicken Council/ 25 (max. 50 in 24 hr. TWA) Burger King# * Wendy’s 25 * United Egg Producers 25 (max. 50 in 24 hr. TWA) # Potentially adopting NCC guidelines From the practical stand point none of the Animal Welfare Guidelines indicate how the ammonia emissions are going to be calculated.

16. American Humane Assoc. Standards • Ammonia. <10 ppm ideal, not exceed 25 ppm. Measure & record weekly • Carbon dioxide. <5000 ppm • Carbon monoxide. <150 ppm • Dust. < 5 mg/cu m (respirable) and <15 mg/cu m (total)

17. Good management practices • Use nipple drinkers. • Use litter material with high water holding capacity. Coarse litter texture can increase the incidence of contact dermatitis compared with fine, soft quality litter. • When the house has concrete floors used no more than 2 inch thick litter (Ekstrand et al., 1997). • Rearing density should be maintained according to the ventilation capacity of the building. • Keep a good ventilation rate in winter. • Minimize overdrinking in breeders by provision of pecking substrates.

18. Minimum standards for humans Regulations NH3 ppm Source UK 25 Charles, 1980 Sweden* 25 DFG, 1999 * Limit of 50 ppm for 5 min exposure Germany 20 DFG, 1999 US 25 ACGIH TWA 35 ACGIH STEL 300 (Dangerous to life)

19. Effects on human health “ increase the susceptibility of the respiratory system to airborne pathogens synergistically at concentrations below the occupational exposure limit of 25ppm” Aerial pollutants and the health of poultry farmers. Whyte, WPSJ 1993.

20. Effects on human health* • Dose-response study of 257 poultry workers to exposure to dust, endotoxin and ammonia • Ammonia exposure levels ranged from 0-75 ppm with 21% of workers exposed to levels exceeding 25 ppm TWA • Concluded threshold concentration for human health (no impaired respiratory function) inside houses is 12 ppm • * Occupational health hazards and recommended exposure limits for workers in poultry buildings. Donham, NPWMS, 2000.

21. Effects on human health* • University of Maryland School of Public Health in cooperation with the Delmarva Poultry Justice Alliance plans to survey poultry growers. • Objective of the survey is to correlate exposure (ammonia, dust) to grower health.

22. Methods to reduce worker exposure to ammonia • Reduce ammonia volatilization! • Limit time growers are exposed to ammonia? • Increase ventilation rate (increase emissions)? • Promote education on respiratory protection!

23. Issues relating to emissions of “odors’ from poultry and swine facilities • Mental and physical health • Decreased property values • Stressed neighbor relations • Civil rights concerns

24. Studies of people living near swine operations report having… • Higher levels of tension, depression, anger and fatigue • Higher incidence of headaches, runny noses, sore throats, excessive coughing, diarrhea and burning eyes

25. Be Aware… • In 1998 Iowa Supreme Court ruled their “Right-to-Farm” was unconstitutional • The Governor has requested a thorough literature review of health effects of emissions from houses • Issue being driven by neighbors-relations concerns

26. Be Aware… • On 9/9/01 jury award 21 neighbors of Buckeye Egg Farm $19.7 million due to nuisance odors and flies. • $4 million compensatory damage (loss of property use and value) • $15.7 million punitive damage for wrongful acts • Sierra Club also filed notice of intent to sue alleging Buckeye emits tons of ammonia without reporting toxics release under CERCAL and EPCRA

27. Be Aware… • Know of 3 cases involving nuisance issues from tunnel ventilated farms

28. NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 NH3 Winter Summer • Low ventilation rate = Higher ammonia accumulation within the house