NEED WE BE CONCERNED ABOUT TOXIC FERTILIZERS?

by Stuart Lieberman
International Real Estate Digest

Recently, much has been written about the safety of fertilizers sold for residential and farm use. We have learned that some of the fertilizer being sold directly to the nation’s farmers, and in some instances to companies that manufacture residential fertilizers, may contain hazardous industrial wastes, sometimes at dangerous levels.

Six of twenty fertilizer products that were tested in 1998 contained undisclosed toxic chemicals which were derived from industrial waste. Three products contained particularly high levels of dangerous wastes. One product contained very high cadmium levels. Another contained very high lead and arsenic levels. The third contained excessive zinc levels.

How and why does this happen? It happens because industrial manufacturers end up with waste as a result of their operations. Often, the waste has hazardous levels of metals and other substances. Normally, the manufacturers must pay a company large sums of money to properly dispose of such hazardous wastes. Thus, as a normal rule, industrial waste represents a fixed cost to the manufacturing concern — it generally is not a saleable asset.

However, in certain cases the waste can be re-sold for a beneficial use, such as, in this case, fertilizer. When the waste is sold to a farm or a fertilizer company, many of the same laws that apply to disposed of hazardous waste do not apply. And, when fertilizer companies re-sell this material to all of us, under current law there is no need to reveal that the material originated as a hazardous waste from some company’s waste stream.

Often, environmentalists encourage re-use, rather than disposal. The problem is that re-use should not result in a health threat. The question now raised, and thus far not answered, is whether the use of industrial waste in fertilizers can make people sick either by contaminating food grown in the fertilizers, or by leaching into ground water and affecting drinking water.

Now there is even more reason for concern. A study published in a recent edition of Environmental Science and Technology Magazine suggests that certain fertilizers may also contain another harmful substance, called perchlorate. Perchlorate is traditionally used to manufacture explosives and other products. The substance has been found in drinking water throughout the country and has long been a concern to scientists. The just published study suggests that fertilizer, at least certain kinds, may contain this substance as well.

I asked the Fertilizer Institute, the trade association for those in that business, to comment. As to the perchlorate issue, the Institute presented what appeared to be good reasons to question some of the study’s findings, conclusions, and methodologies. The Institute’s logic, as to the perchlorate issue, seems to be well grounded. This means that the perchlorate concerns, as they relate to fertilizer, probably should not concern the general public.

As to the industrial waste issue, the Institute explained that nitrogen, phosphorous and potassium are required in the largest quantities in most fertilizers. These three nutrients are regarded in the industry as the “major nutrients” and they comprise about 98 percent of the fertilizer that is sold in United States.

In addition to these three major nutrients, I am informed that there are three secondary nutrients, which are calcium, magnesium and sulphur. In addition, there are several micro-nutrients which include boron, copper, iron, zinc, manganese, molybdenum and chlorine, all of which plants use in very small quantities. According to the Fertilizer Institute, this industrial waste recycling issue really focuses on the micro-nutrient products, because some of these micro-nutrients are derived from recycled industrial waste.

As to whether this kind of operation poses a threat to human health, the Fertilizer Institute informed me that in the past two years three separate risk assessments have been performed to address the issue of human health concerns relating to metals contained in fertilizer products. The most recent was sponsored by the EPA and a draft version can be found on the EPA website. If you have an interest in this issue, I suggest that you go to the EPA website as it has published several reports concerning this issue. All three reports conclude that there is little risk attributable to contaminants found in fertilizers.

The September 1999 EPA report concludes that out of the “large number” of fertilizer products that it considered, only a few represented either unacceptable cancer risks or other health risks. Moreover, where risks were identified, the EPA reported that it was usually one product in a study that skewed the sample results.

As to the need for state regulation, the Fertilizer Institute believes that state officials should have the tools necessary to ensure that products sold within their states are safe when properly used. The Institute concludes, based on the EPA’s September draft report, that there is no basis for taking regulatory action with regard to the vast majority of fertilizers. “Rather, the agency is now focusing attention on whether to modify current regulations governing hazardous waste as a source of a few micro-nutrient products.”