The good news is that cement demand is up in the United States, resulting in kiln additions, plant modernizations, and-in some cases-total plant replacement. The bad news is that, while demand is up, increased cement production can result in higher levels of persistent organic pollutants (POPs) and persistent bio-accumulative toxic chemicals (PBTs), the undesirable byproducts of the combustion process. Regardless of industry's technical or production-related improvements in lowering POP and PBT emissions, regulatory authorities worldwide are attempting to virtually eliminate the generation of POPs and PBTs due to their affinity to accumulate in fat and move up the food chain.

During this current growth and expansion, cement manufacturers may face a spectrum of environmental issues, possibly including renewed opposition to using waste-derived fuels (including hazardous and non-hazardous wastes) as an alternative fuel source. However, there are strategies that the cement industry can integrate into its operations that will manage environmental concerns and at the same time maintain and perhaps improve operating margins.

According to U.S. Environmental Protection Agency (EPA), POPs are recognized as a special problem because they "persist in the environment, accumulate in the fatty tissues of most living organisms, and are alleged to be toxic to humans and wildlife, even at extremely low levels. POPs are prone to long-range transboundary atmospheric transport and deposition that cause significant adverse human health or environmental effects near to and distant from their sources."

The PBTs of interest to the cement industry include certain heavy metals (i.e., mercury and lead) and other chemicals that are formed during the combustion process. Several states, including Washington, have initiated programs to monitor POPs/PBTs by establishing their own lists and asking residents and industry to add to those lists. Washington's initiative on PBTs has resulted in lists that are more expansive than EPA's list.

In 1998, 32 countries, including the European Union, the Russian Federation, the Newly Independent States, Central and Eastern Europe, Western Europe, Canada, and the United States signed two protocols to the Convention on Long-Range Transboundary Air Pollution to reduce and virtually eliminate emissions and discharges of POPs/PBTs. In addition, numerous environmental groups have information about POPs/PBTs on their web sites (see p 40).

Toxicologists have observed that the lay public tends to believe that cement plants that use waste-derived fuels produce more POPs/PBTs. Since coal-fired kilns also release POPs/PBTs, these concerns could show up during the compliance process when the industry petitions to build new cement plants or modernize existing plants.

Any time there is a combustion process, there will be emissions, and the degree to which cement manufacturers manage those emissions is critical. Without management, there will be an increase in the emission of POPs/PBTs, such as dioxins and furans, metals, octachlorostyrene, and hexachlorobenzene, as well as a corresponding increase in residents' concerns about possible adverse health effects.

POPs/PBTs are created during clinker production, which requires very high temperatures of 2,900degrees F, followed by a cooling-off period. As the residual hot air is passed through air pollution control devices, heat-activated molecules look for something to bond to, such as another atom. In doing so, they form new compounds, e.g., dioxins and furans.

Some POPs/PBTs are alleged to disrupt the endocrine system. Environmental activists have reported that when male carp are exposed to certain POPs/PBTs, they take on the characteristics of the female carp. These activists have speculated that, like the canary in the coal mine, human males could be experiencing reproductive effects due to exposure to POPs/PBTs. There also is mounting concern about disorders and diseases of the nervous system and the immune system.

When residents find themselves at odds with industry concerning pollution and possible adverse health effects, the stridency of debate diminishes the possibility of finding common ground. In order to validate their cause with regulators and news media, citizen activists may search for "scientific" data to prove their beliefs. The news media reports and, in some cases, exacerbates the conflict, reporting "junk science" without objective research and analysis. In response to voters, government may over-regulate to assuage voter concerns.

As the cement industry expands to meet demand in the United States, cement company management should prepare for regulatory and environmental group intervention regarding POP/PBT production, which could, in turn, reignite the debate about hazardous waste as alternative fuel source.

One management strategy is to construct a scientifically based, objective assessment process. This should include stating specific goals and objectives, initiating a scientifically sound research plan, and developing experimental protocols to determine at what dose, exposures, and conditions these chemicals might cause adverse health effects. Another approach would be for facilities to conduct multi-pathway risk assessments where stack and fugitive emissions are assessed. These are typically single-source studies that analyze one company at a time and the effect that company's emissions have on a specified locale. Both types of studies should be free from subjective political agendas.

The multi-pathway risk assessment will be interpreted next to other ongoing work, such as the EPA's collaboration with local and state agencies to conduct regional or national modeling studies to better understand the environmental and public health risks from toxic air pollution.

EPA calls this initiative its Cumulative Exposure Project (CEP). At present, these initial CEP studies use hazardous air pollutant data from 1990. However, these studies soon will be updated using 1996 air data. Eventually, the CEP will consider multi-pathway exposures. This data will continue to be used to classify regionalrisk levels. The availability of this information will require cement facilities within particular regions to evaluate the true nature of their contribution to the overall risk of disease. Cement companies that use hazardous waste-derived fuel already have performed some of their homework since they were required to conduct multi-pathway human health risk assessments under Part B Permitting as mandated by provisions of the Resource Conservation and Recovery Act (RCRA).

We know much more about how chemicals interact with human tissue from recent advances in the field of molecular biology. The EPA is on the road to mimic what the U.S. Food and Drug Administration requires prior to a drug candidate being tested in people: pre-clinical toxicological evaluation.

For POPs/PBTs, there probably will be an increasing need for understanding the effect they have on the human body for extended periods. Universities in particular are conducting increasingly complex experiments to provide industry with insights into these issues. Intertox, Inc., a Seattle-based environmental firm, performs toxicology studies and risk assessments estimating potential adverse health effects for 80 or more chemicals, some of which are POPs/PBTs. Through EPA-approved modeling, Intertox scientists are able to predict whether discharged POPs/PBTs have the potential to cause adverse health effects.

The value of this information to cement companies who manage complex chemical processes is that they are able to make sound business decisions by using risk assessment to balance production with potential liabilities. This is particularly important to those companies that are on the brink of extensive plant modernizations and new construction.

For now, cement companies need to focus on metals, dioxins and furan, hexachlorobenzene, octachlorostyrene, PCB, and polyaromatic hydrocarbons. There's a new wave of regulatory activity related to chemicals that persist, bioaccumulate, are stored in fat and move up the food chain. It's reasonable to expect that current lists will expand. For example, Washington is asking for additions to its PBT list.

There are six basic strategies for risk management:

* Keep a finger on the pulse of regulators, public policy organizations, and environmental activists through trade associations and community outreach. Remember that residents have legitimate concerns that need to be addressed.

* Understand the changing landscape of issues: chemical discharge issues are fast becoming a transnational challenge, vis-a-vis the 1998 protocol to the Convention on Long-Range Transboundary Air Pollution, which calls for the elimination of POPs/PBTs.

* Be prepared in the near-term to demonstrate the safety of a product or process.

* Do research designed to understand whether a chemical has an adverse effect.

* Educate neighbors and workers about a plant's environmental initiatives, not because it's required but because it's the right thing to do.

* Adopt the position that knowledge is a tool for growth and the basis for good decisions about when to be proactive.

Persistent organic pollutants (POPs) are highly stable organic compounds (e.g., dioxins, furans) some of which are generated unintentionally as byproducts of combustion and industrial processes. Persistent bio-accumulative toxic chemicals (PBTs) are essentially the same except that the list includes some inorganic compounds. Other POPs and PBTs are pesticides, and do not apply to portland cement plants.

POPs are a special problem because they persist in the environment, accumulate in the fatty tissues of most living organisms, and are toxic to humans and wildlife. POPs with these characteristics are typically semi-volatile, enabling them to move long distances over the earth. These properties lead to increased concern for the toxic effects that they can exert on a range of biota, in particular on top-of-the-food-chain species, even at extremely low levels in the ambient environment. Source: Office of Pesticide Programs, U.S. Environmental Protection Agency.

Priority POPs and PBTs specific to cement Mercury

Alkyl lead

Dioxins and furans

Hexachlorobenzene

Octachlorostyrene

Benzo(a)pyrene

Hexachlorobenzene

Polychlorinated biphenyls

State of Washington list of PBTs (as of Nov. 15, 1999) Anthracene

Benzo(a)pyrene

Benzo(ghi)perylene

Benz(a)anthracene

Cadmium and compounds

1,4-dichlorobenzene

3,3-dichlorobenzidine

Hexachlorobenzene

Mercury and compounds

Pentachlorophenol

Perylene

Phenanthrene

Polychlorinated dibenzo-p-dioxins and furans

For more information on persistent organic pollutants, check out these web sites:

United Nations Environment Program

http://irptc.unep.ch/pops/

Sierra Club

http://www.sierraclub.com

The Joint UNEP Chemicals/WHO-GREENET Project

http://irptc.unep.ch/pops/

Natural Resources Defense Council

http://www.nrdc.org/

National Wildlife Federation

http://www.nwf.org/

Physicians for Social Responsibility

http://www.psr.org/pops.htm

Environment Canada

http://www.ec.gc.ca/envhome.html