Surface Water Quality Bureau
Monitoring & Assessment
Fish Consumption Advisories
Fish are nutritious and are an important part of a healthy diet. However, some fish may contain contaminants at levels that could lead to health problems.
These fish consumption advisories are designed to reduce the risk of adverse health effects or health problems from eating fish caught in New Mexico waters. These advisories are based on the risk from eating contaminated fish and do not take into consideration the health benefits of eating fish. The State of New Mexico recommends eating fish that are low in contaminants. However, there are no contaminant-related health risks from activities such as catch and release fishing, swimming, boating, or camping in and around waters that have fish consumption advisories. Therefore, the State of New Mexico encourages these activities as enjoyable forms of recreation.
The State of New Mexico periodically collects fish from water bodies across the State and analyzes those fish for contaminants. Based on the results of those analyses, we have developed recommendations for fish consumption (expressed in meals per month). The advisories presented here replace previously issued advisories. As new data become available, we will update these advisories.
Department of Game & Fish
Department of Health
In some New Mexico fish, three particular contaminants have been detected at levels that could result in health problems from long term fish consumption, such as for weeks, months, or longer. These contaminants are mercury, polychlorinated biphenyls (PCBs), and dichloro-diphenyl-trichloroethane (DDT). Eating fish for which there is a consumption advisory may not make you feel sick, but long term consumption of such fish could increase your risk for a variety of health problems.
Mercury is a very toxic metal. In fish, mercury is in the form of methylmercury. Methylmercury is toxic at very low exposure levels. Eating fish is the main way that people are exposed to methylmercury. However, each person’s exposure depends on the amount of methylmercury in the fish they eat and how much and how often they eat fish.
If too much methylmercury is consumed, over a long period of time, it damages the brain, nerves, kidneys, and may lead to other health problems such as those of the cardiovascular system. The brain of fetuses, babies, and young children are most at risk as they are still developing. All prenatal effects of exposure to mercury have been found to be permanent. The developing fetus and breast-fed babies are vulnerable to toxic effects of their mother’s mercury exposure because many aspects of their development, particularly brain maturation, can be disturbed by the presence of mercury. Developing babies exposed in the uterus may suffer from mental retardation, lack of coordination, blindness, seizures, speech disorders, and learning disabilities. Young children are also less able to detoxify and excrete mercury from their bodies. Thus, people most at risk for health problems related to mercury are women who are pregnant or nursing, women who may become pregnant, and children age six and younger, so they should only eat fish low in mercury. This consumption advice for mercury-contaminated fish is intended to protect children and pregnant or nursing women. For others, this advice may be overly protective.
Methylmercury accumulates in fish over the course of their lifetimes, so older (and, typically larger) fish tend to have more mercury than younger (smaller) fish. This is why, within a species at a particular lake, larger fish tend to have a lower number of recommended meals per month than smaller fish. Also, fish that eat other fish (predators) tend to have relatively higher mercury concentrations in their bodies than less predatory fish. For example, predatory fish such as walleye, bass, or pike typically have more mercury than trout, bluegill, or suckers (insect or plant eaters).
PCBs are a class of industrial chemicals that were once used as electrical insulators, lubricants, and coolants. In 1978, PCBs were banned from use in the United States. However, unintentional releases, such as fires involving PCB-containing transformers, are a way that they can still enter the environment. PCBs do not break down easily in the environment, which is why they may still present a public health concern today.
Eating too much fish with PCBs may cause a variety of health problems, including those related to nerve development, reproduction, hormones, and cancer. The negative effects of PCBs on development of infants and children whose mothers were exposed before becoming pregnant and during pregnancy are of particular concern. The effects in newborns and children may include a decrease in learning ability that may continue later in life. PCBs may cause cancer in humans, particularly liver and kidney cancer, because they are known to cause cancer in laboratory animals.
The consumption advice for PCB-contaminated fish is intended to reduce one’s lifetime cancer risk. The calculations used to develop this advice assume that if you eat PCB-contaminated fish according to these recommendations, the chances of developing cancer from it are one in 100,000. This advice also protects from other health problems related to PCB exposure.
The consumption advice for DDT-contaminated fish is intended to reduce one’s lifetime cancer risk. The calculations used to develop this advice assume that if you eat DDT-contaminated fish according to these recommendations, the chances of developing cancer from it are one in 100,000. This advice also protects from other adverse health effects from DDT exposure.
You can remove much contamination by properly cleaning and preparing the fish you catch. This is particularly true for PCB- and DDT-contaminated fish. Handling fish will not result in exposure to dangerous levels of contaminants.
First, you should remove the skin, fat, and internal organs. When cooking fish, you can reduce the amount of PCBs and DDT stored in the fatty portion of the fish by grilling, baking, or broiling and letting the fat drip away. However, avoid frying fish, because frying seals in contaminants that may be in the fish’s fat.
Methylmercury is not stored in the fish’s fat, and therefore, there is no cleaning or cooking method that will reduce the amount of mercury in fish.
Some of the fish sizes listed in this advisory are below the legal size limit as established by the New Mexico Game Commission. These advisories are for consumption limits only and do not supersede regulations pertaining to size or possession limits.
For more information about fish advisories, visit the US Environmental Protection Agency at www.epa.gov/waterscience/fish or the New Mexico Environment Department at www.nmenv.state.nm.us/swqb/advisories.
If you have questions about these advisories, please call the New Mexico Environment Department, Surface Water Quality Bureau at (505) 827-2470 or toll free at (866) 885-2997. If you have questions about health concerns related to consumption of contaminants, please call the New Mexico Department of Health, Environmental Health Epidemiology Bureau at (888) 878-8992. If you have questions about fishing opportunities or regulations, please call the New Mexico Department of Game & Fish at (505) 476-8000 or toll free at (800) 862-9310.
For more information, please see the US EPA's Fish Advisories Newsletter. This wonderful source of topical news, events, conferences and more is designed to share the latest information related to fish advisories. Each month the newsletter includes topics found in recent newspaper, magazine, and journal articles of interest to the fish advisory community.