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Spring 2002Bulletin
Long Awaited Standardsd Proposed to Protect Human Health
Back in 1979 EPA issued so-called ‘numeric criteria’ – maximum permissible concentration levels in water and fish – for 109 priority toxics, upper limits which were designed to reduce human health risks (from eating contaminated fish or drinking contaminated water supplies) to ‘acceptable’ levels – judged to be one cancer case per 100,000 population or more. In 1987 the Clean Water Act was amended to require that all states, within three years, adopt numeric criteria for all priority toxic pollutants ‘the discharge or presence of which could be expected to cause water quality problems.’ New Mexico is now the only state not to have complied.
The New Mexico Environment Department is proposing to introduce standards for a whole suite of ‘priority pollutants’ never before regulated in New Mexico. Amongst the pollutants are many of the most poisonous toxins known to man – and in fact many are man-made concoctions – such as dioxin, PCBs and a variety of pesticides. The state’s position up to now has been that most of these ‘persistent, bioaccumulative’ pollutants are not found in New Mexico; but the Environmental Protection Agency has decided that the framework should be in place to regulate them anyway. The Environment Department’s Surface Water Quality Bureau will petition the Water Quality Control Commission to make the necessary changes at a March 12-13 hearing in Santa Fe.
The state has said that there is no point in regulating pollutants that are not known to exist in New Mexico, or which exist in such small quantities that they cannot be ‘expected to cause water quality problems.’ EPA has pointed to the state’s inadequate sampling and monitoring system, and in a preliminary screening of its own found 24 of the unregulated priority pollutants.
The prevailing scientific view is that these PBTs (persistent bioaccumulative toxins) are so poisonous that a precautionary approach should be taken in regulating them. This means erring on the side of caution: where there are recognized uncertainties, we should take a conservative approach to protect human health and the environment. Because these substances are bioaccumulative, they can reach far higher (unpredictable) levels in fish than in the discharge or the surface water itself; and because they are persistent and do not break down in the environment – as the history of DDT made famous – they can ‘travel’ far in biological food webs with unpredictable and dangerous consequences. Their synergistic effects, from acting in combination, are even more poorly known. The EPA ultimately has a precautionary, zero-discharge goal for priority toxics: “We recognize… that because these pollutants are so harmful, it makes most sense over the long term to prevent future contamination.”
In this precautionary context, the Surface Water Bureau’s proposal is therefore very welcome. Monitoring is being boosted in order to give an assurance of fully detecting these substances. Even if most of the toxins are not immediately detected in significant concentrations, the framework will be in place to regulate them if they are found in the future. The new controls will apply most strongly to NPDES permits, mainly for discharges from industry and municipalities, preventing the toxins from reaching most surface waters. EPA points out that cutting off the contaminants at their source will benefit a wide variety of water quality protection programs – “fish tissue quality protection, non-point source controls, drinking water quality protection, and ecological protection.”
Clearly, PBTs should be prevented from ever entering natural and human food chains wherever possible, and should be actively sought out and controlled rather than waiting helplessly for proof of their impacts. Other judgments about them are not so easily arrived at. Although the Bureau is in most cases using EPA’s extensive toxicological research to set the concentration limits, or numeric standards, it is suggesting an acceptable cancer risk level of 1:100,000, as opposed to EPA’s, and many states’, level of one per million. Less stringent limits are also being proposed for arsenic, a carcinogen which admittedly is naturally-occurring in many, but not all, parts of New Mexico. The proposal requires regulation only of priority toxics “from other than natural causes”, without seeming to be aware of the difficulty of discerning natural from man-made sources in composite situations. (Amigos Bravos is very aware of this problem. Contaminated seeps emanating from Molycorp’s mine site, presumably derived from some combination of natural and non-natural pollution sources, are being regulated by EPA as if all the contaminants were from Molycorp’s operations – a sensible application of the precautionary principle for protecting the environment under prevailing uncertainty from whatever source, pending better determination of exact origins.) And the supposed control of non-point source toxics (agricultural pesticides might be an example) through the TMDL program, and therefore through voluntary compliance, seems weak for regulating these extremely harmful substances.
Having said all that, the present petition is a very positive step in the right direction. At least 70 of the most poisonous substances on the planet will be regulated for the first time in New Mexico; and at least seven previously regulated poisons – which are known to exist in New Mexico – will be more strictly controlled than before. This can only benefit our environment and our health, with over 50 of the regulated substances being known carcinogens and all of them having serious human health effects.
If you have the opportunity, your own input in support of the Bureau’s petition at the March 12-13 hearing could be influential. (Amigos Bravos will put out a detailed action alert on our website close to the scheduled time.) We may want to quibble about the details at a later date, but right now it is important to take that first crucial step, and make sure this petition is passed.
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