Use of Lead Fishing Tackle and Lead Shot in Canada

May 28, 2021

Position

The Canadian Veterinary Medical Association (CVMA) strongly supports a ban on the use of lead fishing weights, jigs and lead shot because of the direct and indirect harm they may induce in humans, wildlife and the environment.  The CVMA strongly supports the development and use of non-toxic materials for hunting and angling purposes.

Summary

  • The use of lead shot and lead fishing tackle, such as weights and jigs, is a One Health concern.
  • Lead toxicity has been well described in wildlife species, especially waterfowl and raptors.
  • Repeated exposure to lead in ammunition and fishing gear causes harm to human health.
  • Lead is stable in most soils and breaks down via oxidation very slowly, if at all.
  • It is still legal to use lead shot for some upland game hunting, for target shooting and to use or possess lead fishing sinkers and jigs outside of national parks and wildlife areas.
  • A complete ban is recommended as partial bans are not as effective due to difficulties with enforcement and reduced incentive to produce non-toxic alternatives.
  • Non-toxic alternatives such as bismuth, steel, tin, or clay can be used for fishing weights and shot, and their use should be promoted.

Background

  1. The CVMA supports the concept of One Health, which recognizes the interconnectedness of human, animal and environmental health.
  2. In Canada, lead was one of the first substances to be added to the List of Toxic Substances (Schedule 1) in the original 1988 Canadian Environmental Protection Act (CEPA).
  3. Lead toxicity has been well described in wildlife species, especially waterfowl and raptors, with historical annual losses estimated at 2.5 million birds in North America before bans were introduced (1).

    a. Swans and other waterfowl are known to ingest spent lead shot. Loons ingest lead fishing weights or jigs, mistaking it for food or grit while feeding at the bottom of lakes or ponds or in agricultural fields.   In some species, such as the common loon (Gavia immer), lead toxicity is the leading cause of mortality (1,2).

    b. Avian predators and scavengers, such as eagles, hawks, great horned owls, vultures, and condors, can be inadvertently poisoned after eating sick, dead, or crippled game birds, or hunter-discarded carcasses of ungulates or rodents that contain embedded lead ammunition fragments (3−7).

    c. Terrestrial bird species reported to ingest spent lead shot with subsequent toxicity include mourning doves (Zenaida macroura), ring-necked pheasants (Phasianus colchicus), northern bobwhite quail (Colinus virginianus), wild turkey (Meleagris gallopavo), American woodcock (Scolopax minor), and chukars (Alectoris chukar). These species may consume lead shot as they feed on seeds on the ground or when they ingest small stones as grit, especially in heavy hunting areas or areas in which high densities of lead shotgun pellets accumulate in soil and sediment (e.g., clay target shooting ranges) (3,6,8).

    d. More than thirty species of birds and 4 non-human mammal species have been documented to ingest lead fishing gear (9).

    e. Lead poisoning and elevated lead concentrations in tissues have been reported in waterfowl, perching birds, small mammals, and frogs at trap and skeet ranges (10).

  4. The clinical effects of lead poisoning in birds are well-documented (1,7,11-13).

    a. Birds with lead poisoning often have physical and behavioural changes, including loss of balance and inability to fly. Even when overt signs of lead poisoning are not present, birds may still have trouble feeding, mating, nesting, and caring for young.

    b. Acute toxicity can occur after the ingestion of a single lead sinker or lead-headed jig and can result in the death of the bird within a few days.

  5. Regarding human health, the World Health Organisation states that “there is no level of exposure to lead that is known to be without harmful effects”, particularly in children and women of reproductive age (14). Adverse health and cognitive impairments occur at even very low levels (15). There is abundant evidence that continued use of lead-based ammunition and fishing gear causes significant health risks for regular consumers of wild game and fish.

    a. Lead shot and bullets shatter into small fragments on impact. The particles are widely distributed in game tissues, and the contaminated meat is subsequently eaten (16-18).

    b. Hunters are subject to elevated exposure to lead from the discharge of firearms (19).

    c. Anglers may ingest lead directly or indirectly by biting down on split shot, or simply by handling lead sinkers (9).

    d. Homemade fishing weights prepared by melting lead cause a public health risk through inhalation (9). The molds to make these weights are readily available.

    e. Accidental lead sinker ingestion by children and pets has been documented by poison control centres (9).

  6. Lead shot is stable in most soils and breaks down via oxidation very slowly, if at all (20,21). In some areas, the amount of lead deposited in the environment from hunting and target shooting have led to classification of the surrounding soil as a hazardous waste (9).
  7. It is estimated that 545 tonnes of lead jigs and sinkers are lost annually in Canadian lakes and waterways (22).
  8. Canada has required that non-toxic (non-lead) shot be used: in national wildlife areas since 1995, in wetlands since 1997, for hunting most migratory game birds across the nation since 1999, and for upland game birds since 2012.

    a. Lead exposure in ducks in Canada has declined dramatically since non-toxic shot regulations were established (23).

    b. In Canada it is now illegal to use or possess lead fishing sinkers and jigs in national parks and wildlife areas.

    c. The use of lead shot is still legal for some upland game hunting, and for target shooting.

  9. In Canada it is still legal to use or possess lead fishing sinkers and jigs outside of national parks and wildlife areas.
  10. Partial bans are not as effective as full bans due to difficulties with enforcement and reduced incentive to produce non-toxic alternatives, therefore CVMA supports a complete ban on the use of lead in sinkers and shot (9,24).

    a. The CVMA supports the educational programs of government agencies and interest groups that inform the public about the hazards of lead.

    b. Non-toxic alternatives such as bismuth, steel, tin, or clay can be used for fishing weights and shot, and their use should be promoted (25).

References

  1. Rattner BA. History of wildlife toxicology. Ecotoxicology 2009;18:773-783. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19533341.
  2. Scheuhammer AM, Norris SL. A Review of the Environmental Impacts of Lead Shotshell Ammunition and Lead Fishing Weights in Canada.  Canadian Wildlife Service Occasional Paper No. 88, Environment Canada, Ottawa. 1995, 54 pp; Available from: http://publications.gc.ca/collections/Collection/CW69-1-88E.pdf
  3. Scheuhammer AM, Money SL, Kirk DA, Donaldson G. Lead fishing sinkers and jigs in Canada: Review of their use patterns and toxic impacts on wildlife. Canadian Wildlife Service Occasional Paper no. 108, Environment Canada, Ottawa. 2003, 48 pp; Available from: http://www.collectionscanada.gc.ca/eppp-archive/100/200/301/environment_can/cws-scf/occasional_paper-e/n110/html/publications/AbstractTemplate.cfm@lang=e&id=1031
  4. Kendall RJ, Stansley W, Leighton F, et al. An ecological risk assessment of lead shot exposure in non-waterfowl avian species: Upland game birds and raptors. Environmental toxicology and chemistry 1996;15:4-20. Available from: https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1135&context=usepapapers
  5. Fisher IJ, Pain DJ, Thomas VG.  A review of lead poisoning from ammunition sources in terrestrial birds. Biol Conser 2006;131:421-432. Available from: http://europepmc.org/article/PMC/3672933.
  6. Hunt WG, Burnham W, Parish CN, Burnham KK, Mutch B, Oaks JL. Bullet fragments in deer remains: Implications for lead exposure in avian scavengers. Wildlife Society Bulletin 2006;34:167-170. Available from: https://science.peregrinefund.org/legacy-sites/conference-lead/PDF/0112%20Hunt.pdf
  7. Church ME, Gwiazda R, Risebrough RW, et al. Ammunition is the principal source of lead accumulated by California condors re-introduced to the wild. Environ Sci Tech 2006;40:6143-6150. Available from: https://www.ncbi.nlm.nih.gov/pubmed/17051813
  8. Runia, TJ. Spent lead shot availability and ingestion by ring-necked pheasants in South Dakota. Wildlife Society Bulletin 2016;40:477-486 Available from: https://link.springer.com/article/10.1007/s13280-019-01159-0
  9. Grade, T., Campbell, P., Cooley, T. et al. Lead poisoning from ingestion of fishing gear: A review. Ambio 48, 1023–1038 (2019). Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6675807/
  10.  Hui CA. Lead distribution throughout soil, flora, and an invertebrate at a wetland skeet range. J Toxicol Environ Health A. 2002;65:1093-1107. Available from: https://pubmed.ncbi.nlm.nih.gov/12167221/
  11. De Francisco N, Troya JR, Agüera EI. Lead and lead toxicity in domestic and free living birds.Avian Pathology 2003;32:3-13. Available from: https://www.tandfonline.com/doi/abs/10.1080/0307945021000070660
  12. Ecke, F. Sublethal lead exposure alters movement behavior in free-ranging Golden Eagles. Environmental Science and Technology 2017;51:5729-5736. Available from: https://pubs.acs.org/doi/pdf/10.1021/acs.est.6b06024
  13. Gil-Sanchez, JM. From sport hunting to breeding success: Patterns of lead ammunition ingestion and its effects on an endangered raptor. Science of the Total Environment 2018; 613:483-491. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0048969717324117
  14.  WHO, 2017. Lead Poisoning and Health. Available from: http://www.who.int/mediacentre/factsheets/fs379/en/.
  15. Health Canada, Risk Management Strategy for Lead, February 2013. Available from: https://www.canada.ca/en/health-canada/services/environmental-workplace-health/reports-publications/environmental-contaminants/risk-management-strategy-lead.html
  16. Pain D.J., Cromie R.L., Newth J., Brown M.J., Crutcher E., Hardman P., Hurst L., Mateo R., Meharg A.A., Moran A.C., Raab A., Taggart M.A., Green R.E. 2010. Potential hazard to human health from exposure to fragments of lead bullets and shot in the tissues of game animals. PLoS ONE, 5 (4): 1-17. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2859935/
  17. Health Risks from Lead-Based Ammunition in the Environment. Environmental Health Perspectives, 2013. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3672933/#r14
  18. Proceedings of the Oxford Lead Symposium. Lead ammunition: understanding and minimizing the risks to human and environmental health. 2014. Available from: http://oxfordleadsymposium.info/proceedings/.
  19. National Research Council. 2012. Potential Health Risks to DOD Firing-range Personnel from Recurrent Lead Exposure. National Academies Press, Washington, D.C Available from: https://www.ncbi.nlm.nih.gov/books/NBK206966/
  20. Pattee OH, Pain DJ. Lead in the environment. In: Hoffman DJ, Rattner BA, Burton Jr, GA, Cairns Jr, J, eds. Handbook of Ecotoxicology. 2nd Ed. Boca Raton, Florida: Lewis Publishers, CRC Press LLC, 2003:373-408.
  21.  Henny CJ. Effects of mining lead on birds: A case history of Coeur d’Alene Basin, Idaho. In: Hoffman DJ, Rattner BA, Burton Jr, GA, Cairns Jr, J, eds. Handbook of Ecotoxicology. 2nd Ed. Boca Raton, Florida: Lewis Publishers, CRC Press LLC, 2003:373-408.
  22. Environment and Climate Change Canada. Study to gather Use Pattern Information on Lead Sinkers and Jigs and their Non-lead Alternatives in Canada. 2018. Available from: http://publications.gc.ca/collections/collection_2018/eccc/En14-308-2018-eng.pdf
  23.  Stevenson AL, Scheuhammer AM, Chan HM. Effects of lead shot regulations on lead accumulation in ducks in Canada.  Archives Environ Contam Toxicol 2005;48:405-413. Available from: https://pubmed.ncbi.nlm.nih.gov/15719196/
  24.  Kanstrup, N. Lessons learned from 33 years of lead shot regulation in Denmark. 2019. Ambio 48:999-1008. Available from: https://pubmed.ncbi.nlm.nih.gov/30506141/
  25. McCann, BE. Efficacy of non-lead ammunition for culling elk at Theodore Roosevelt National Park. Human-Wildlife Interactions 2016;10:268-282 Available from: https://digitalcommons.usu.edu/hwi/vol10/iss2/11/