Fishing Advisories and Fish Contaminants

EEES 4730Amanda Wendzicki

Objective

• To discuss the purpose of fish advisories, the effects and origins of the contaminants, and propose possible solutions

• A warning put out by governing bodies that people limit or avoid eating certain species of fish from certain bodies of water.– May coincide with

commercial fishing bans

Fishing Advisory

• Due to the level of contaminants within a body of water.

• May be targeted toward specific demographics– Largely, women who

are pregnant or who may become pregnant and small children

Cause for concern• Many contaminants end up within water bodies

by means of runoff from improper containment or disposal practices, or straight discharge from industry.

• Many harmful compounds are long lasting within the aquatic environment.

• Bioaccumulation causes for an increased concentration of the contaminants within predatory species.

• Many also lend to developmental problems in humans as well as wildlife.

Contaminants

• 5 primary contaminants– Mercury– PCBs– Chlordane– Dioxins– DDT

• Long lasting in sediments

• Accumulate in bottom-dwellers

• Become more concentrated in fish by bioaccumulation as you move up the trophic levels

Mercury

• Particularly of concern due to developmental consequences for:– Women who are or may become pregnant– Nursing mothers– Young children

• Much of the mercury originates with coal-burning power plants

Minamata Disaster

• Kyushu Japan, 1950s, Chisso Corporation (petro chemical company)– Discharge of mercury laden waste water into local

waters– As of march 2001, 2265 victims

PCBs

• (Polychlorinate Biphenyl)– Common coolant– Most commonly observed health

affects• Skin conditions• Indicators of liver damage

• Yusho disease• Kyushu Japan, 1968• Rice bran oil became contaminated• Got into chicken feed

Chlordane

• Sold in US until 1983 as an insecticide

• Associated with testicular and prostate cancer among other cancers

Dioxins

• By-products of various industrial processes

• Effect on humans relatively unstudied

• Expected adult reactions:• Liver damage• Diabetes• Immunological effects

• Developmental issues believed to be greater• Effecting sexual

development

DDT

• Synthetic insecticide• 1962 Silent Spring– Raised public awareness of effects

• Persistent organic pollutant • Known for eggshell thinning of predatory birds• Linked to broad developmental problems in

humans

Possible solutions• Those contaminants that have been pesticides

have since largely been discontinued within the US and replaced with safer alternatives.– They still remain an issue in developing countries due

to their relative cost and effectiveness• For those that are industry born, stricter

regulation and enforcement could aid in the prevention of these contaminants reaching aquatic habitats.– Only discontinued use could end new contamination,

and little can be done to remove current contamination once it has been bio accumulated

National Lake Fish Tissue Study

• Statistically based surveys conducted by EPA since late 1990s

• Randomly selected lakes and reservoirs in lower 48 states

• Divided into 6 size categories

• Collected composites of one predator species and bottom-dwelling species

• 5 adults• Analyzed each

composite for 268 chemicals

• Created to provide baseline information to track future changes

• Mercury and PCBs were present in every fish sample

• 49% of entire sample population exceeded EPA’s quality criteria of 0.3ppm of mercury

• 43 of 268 chemicals tested for not detected

"Water: Fish Advisories." Home | Water | US EPA. Environmental Protection Agency. Web. 03 Nov. 2011. <http://water.epa.gov>.

The National Study of Chemical Residues in Lake Fish Tissue. Washington, DC: United States Environmental

Protection Agency, Office of Water, Office of Science and Technology, 2009. Print.

"Human Health: Fish Consumption -- Critical Contaminants." Great Lakes Information Network. Web. 03 Nov. 2011. <http://www.great-

lakes.net/humanhealth/fish/critical.html>.