Major New Study Bolsters Leahy's Mercury Control Bill

July 11, 2000

WASHINGTON (Tues., July 11) – A major new study released today by the nation's premier scientific panel buttresses Senator Patrick Leahy's longstanding concerns about the harmful health effects of mercury, and Leahy believes the report will add momentum to his bill to limit mercury in the environment.

The study, by a committee of the prestigious National Academy of Sciences, comes after an 18-month review of the science used by the U.S. Environmental Protection Agency (EPA) in proposing new guidelines for protecting the public – and especially sensitive populations such as pregnant women and children – from contamination that many receive by eating fish.

The scientists conclude that EPA's guidelines for fish consumption by these groups -- and not the less stringent standards adopted by the FDA and by another federal agency -- are supported by the evidence.

Leahy has long been Congress's leader in battling for standards to limit mercury in the environment. He has introduced the first complete mercury pollution control bill, The Omnibus Mercury Emissions Act, and he also has authored The Clean Power Plant and Modernization Act, which would cut mercury emissions from the Midwest's coal-fired powerplants, which are the leading source of mercury pollution in Vermont and the nation. Special interests have delayed action on mercury pollution for decades, most recently by mandating this study.

"There are no more excuses. It is time to cut mercury pollution and protect Americans' health," said Leahy. "Mercury is the last major toxic substance without an emissions control plan. For years Congress and the special interests have kicked the ball down the field. This report brings us to the goal line, and Congress needs to act in the public's interest and to stop doing the bidding of the special interests."

N E W S B R I E F I N G

National Academy of Sciences Releases Methylmercury Study Confirming Leahy's Concerns That Current FDA Mercury Level

The release today of the National Academy of Sciences (NAS) report ("The Toxicological Effects of Methylmercury") to Congress has confirmed the Environmental Protection Agency's (EPA) most-stringent public health standard for mercury ingestion. The report upholds the EPA's 0.1 microgram per kilogram body weight per day (mg/kg/day) standard and calls into question the higher mercury toxicity levels currently accepted by the Food and Drug Administration (FDA) and Agency for Toxic Substances and Disease Registry (ATSDR).

Methylmercury is a dangerous neurotoxin in humans. Prenatal exposures to methylmercury can cause irreversible damage to the developing central nervous system -- babies born with acute exposures have had severe disabilities, including mental retardation, seizure disorders, cerebral palsy, blindness, and deafness. Several scientific reports suggest that lower, chronic doses of methylmercury -- that is, through high maternal fish consumption -- may result in subtle neurological deficiencies in infants, such as lowered I.Q., abnormal muscle tone, and loss of motor function, among other difficulties. The populations considered most at risk are pregnant women, women of child-bearing age, and small, developing children.

"This report validates the soundness of EPA's scientific methods and standards as well as its commitment to the public's health," Leahy said in a statement. "After several long years of delay and waiting for the last word in scientific evidence, we now have the last word. Congress finally has a uniform mercury standard that we can and should use to attack the real public health issues of mercury in our environment. There are no more excuses for ignoring the potentially damaging effects of methylmercury ingestion."

As confirmed by EPA's 1997 Mercury Report to Congress, Americans are exposed to the majority of methylmercury through fish consumption. In the past, the EPA reference dose for humans was set at 0.1 micrograms of mercury per kilogram body weight per day (mg/kg/day) based on scientific studies of severe mercury poisonings and fatalities around the world.

The FDA's "action level" (the level at which FDA may take legal action to remove a product from the market) has long been 1.0 part per million of mercury in fish tissue, the equivalent of almost 0.5 mg/kg/day exposure in humans and five times the EPA level. Leahy had joined with Senator Tom Harkin (D-Iowa) earlier this year to question the FDA about its high "action level" as well as its sampling methods for safeguarding U.S. populations from fish catches exceeding the FDA level. The FDA response concerned both senators when they learned that, as of 1998, FDA was no longer monitoring domestically-caught fish for mercury, despite several catches exceeding FDA's own level in 1997. The populations most at risk for adverse effects methylmercury toxicity are those defined by the NAS as consuming "high levels" of fish at or near 100 grams per day, or approximately 3.5 ounces per day. Based on statistical samples, the NAS believes that this is the amount of fish eaten by about 5 percent of the U.S. population that consumes fish. The report estimates that, on average, this means that 7 percent of women nationwide would exceed the 0.1 ug/kg/day reference dose for methylmercury. In addition, the risk may be higher in certain regions of the country. For example, in a New Jersey study, 21 percent of women of childbearing age would exceed the 0.1 ug/kg/day reference dose.

The NAS further estimated that these values would place about 60,000 babies at risk for adverse mercury level exposure each year.

Mercury Pollution Bills Authored And Introduced By Senator Patrick Leahy: (S.673) The Omnibus Mercury Emissions Act of 1999 Cuts mercury emissions by over 95 percent from the industries identified by EPA's 1997 Mercury Report to Congress as the most mercury-polluting. Calls on government agencies to monitor and regulate mercury in the environment, including labeling mercury-containing products and actively finding alternatives to mercury in products throughout the country.

(S.1949) The Clean Power Plant and Modernization Act of 1999 Cuts mercury emissions from coal-fired power plants, the single-largest source of mercury emissions, to 90 percent of current levels (from 51 to 5 tons per year).

Senator Patrick Leahy June 10, 2000 Mercury Issue "Timeline"

1969 FDA sets an "action level" for mercury at 0.5 mg/kg/day

1979 FDA sets an "action level" for mercury in fish tissue at 1.0 ppm, said to be equivalent to 0.5 mg/kg/day by National Marine Fisheries Agency assumptions and calculations.

1990 Clean Air Act amendments mandate an EPA "Mercury Study Report to Congress" to be completed by November 1994. Report is to include: -study of mercury emissions to atmosphere -information on mercury accumulations in air, water, and soil -information on sources, effects, and control options for mercury

June 1996 EPA's "Mercury Study Report to Congress" completed as a seven-volume, 1,700 page report that was peer-reviewed internally and externally.

EPA does not release report to Congress or the public, but forwards it to the Science Advisory Board (SAB) for further review. EPA says new studies are expected to be published over the next two years and could be included. October 1996 Senator Patrick Leahy (D-Vt.) leads 20 senators in a letter to EPA calling for the immediate release of the report.

Feb. 1997 The Science Advisory Board (SAB) recommends that EPA need not wait for further data to move forward with the report. SAB also finds that the EPA's report was already the best compilation to date of all data available on mercury in ecosystems and wildlife and supported many of EPA's calculations about which EPA had earlier expressed concerns.

May 22, 1997 Senator Leahy leads a bipartisan coalition of six senators to introduce a Senate resolution that calls for the immediate release of the EPA mercury report and questions the reasons for the delay.

May 22, 1997 EPA publicly announces it will release the report by the end of the year.

Dec. 19, 1997 EPA releases the "Mercury Study Report to Congress." Among other findings, conclusions of the report include: -coal-fired power plants and municipal trash incinerators are among the major sources of mercury emissions that can contaminate fish and birds and, if concentrated at high enough levels, can lead to human neurological damage; -at least 1.6 million Americans are potentially at risk from food contaminated by mercury pollution that enters the environment principally as the result of human activities. -EPA sets reference dose at 0.1 mg/kg/day April 1998 Senator Leahy introduces the "Omnibus Mercury Emissions Reduction Act of 1998" (S. 1915) in the 105th Congress.

The bill would amend the Clean Air Act by requiring a 95% reduction in mercury emissions from coal-burning power plants within five years. Likewise, solid waste incinerators and other industrial facilities would have to strongly limit their mercury emissions. The bill would also require safe disposal of recovered mercury compounds and labeling of mercury-containing products such as fluorescent light bulbs and batteries. The legislation further instructs EPA to publish lists of mercury-containing products and requires the EPA to issue public reports each year about mercury emissions from certain industries.

Summer 1998 Representative Mollahan adds language to House VA-HUD Appropriations bill that says EPA can not regulate mercury until scientific studies confirms an "action level" or "reference dose" level. July 17, 1998 A Senate floor colloquy between Senator Leahy and the late Senator Chafee (R-R.I.) argues that Representative Mollahan's language is an improper use of appropriations process. During conference of the bill, Senator Leahy and Representative Mollahan compromise with language calling for EPA regulations to abide by a National Academy of Sciences study that will be completed as quickly as possible – due July of 2000. Early 1999 Senator Leahy re-introduces his mercury reduction bill, now called the "Omnibus Mercury Emissions Reduction Act of 1999" (S. 673) with Senator Olympia Snowe (R-Maine).

March 1999 Senator Leahy sends a letter to Health and Human Services (HHS) Secretary Donna Shalala urging review of the HHS Agency for Toxic Substances and Disease Registry (ATSDR) proposed "toxicity profile" of mercury.

Leahy suggests that the proposed profile is a weakening of currently-available reference dose information and will cause confusion as to appropriate mercury levels. Leahy argues that ATSDR should submit data to the ongoing National Academy of Sciences study mandated in FY 1999 VA-HUD Appropriations.

ATSDR sets mercury "action level" at 0.3 mg/kg/day October 7, 1999 Senators Leahy and Harkin send letter to Secretary Shalala requesting information from FDA about how the agency is protecting American consumers from the risks of mercury-contaminated food. It also asks for clarification of basis for FDA

They set a deadline for November 5, 1999 for a response.

February 15, 2000 Three months after the deadline, FDA finally responds to the letter from Senators Leahy and Harkin. The FDA letter includes datasets that show FDA has stopped monitoring domestically-caught seafood for mercury contamination in 1998. This was done despite the fact that their 1997 data shows that several samples of domestically-caught tuna, swordfish, and shark that year exceeded their own 1.0 ppm "action level."

May 2000 Senators Leahy and Harkin release a statement expressing serious concerns over the lack of FDA monitoring of domestically-caught seafood since 1998.

July 11, 2000 National Academy of Sciences releases their report, the "Toxicological Effects of Methylmercury" to Congress.

The report support the EPA reference dose for methylmercury at 0.1 micrograms of Hg per kilogram body weight per day (mg/kg/day). This value is five times less than the current FDA action level (0.5 mg/kg/day) and three times less than the current ATSDR action level (0.3 mg/kg/day). The U.S. population is exposed to the majority of methylmercury through fish consumption. In its risk assessment section, the report defines "high consumption" levels of fish at or near 100 grams/day (approximately 3 ounces/day). This is the amount eaten by about 5% of the U.S. populations studied.

Given these statistics, the EPA report estimates that, on average, 7% of women nationwide would exceed the 0.1 ug/kg/day reference dose for methylmercury. In addition, the risk may be higher in certain regions of the country. For example, in a New Jersey study, 21% of women of childbearing age would exceed the EPA's reference dose.

These values would place about 60,000 babies at risk for adverse mercury level exposure each year.