Discussion Paper 

Risks, Rights and Regulation
Communicating about Risks 
and Infant Feeding

MATTER OUT OF PLACE

Because of the widespread pollution of rural and urban environments, some toxic substances such as PCBs, dioxins, phthalates, and heavy metals have been found in samples of breastmilk. As a result of bio-magnification, chemical residues concentrate as they move up the food chain, until they appear in breastmilk. Fat-soluble toxins are removed from the bloodstream and stored in body fat because they are metabolized very slowly. Crash diets during lactation may release these stored toxins into the bloodstream and into breastmilk. Breastmilk incorporates contaminants from maternal body fat; in this way breastfeeding is also the main route for elimination of contaminants from the body of the mother. The most toxic contaminants present in the food supply and breastmilk include: halogenated hydrocarbons, pesticides and fungicides, dioxins and furans, industrial chemicals (halogenated biphenyls), and heavy metals.

Chlorinated pesticides include DDT, the first chemical seen to have an effect on the environment; it was banned in 1972 in the United States. However, rural women in India, China, Guatemala, and Mexico continue to have high levels of exposure. DDT was banned in Norway in 1970, but seven years later, nursing mothers still had detectable levels of DDT in their milk (Berlin and Kacew 1997:73). DDT is still used for malaria control. While malaria kills more than a million people per year, DDT in breastmilk has unknown health consequences. DDT is not supposed to be used for agricultural uses, but is recognized as important in malaria control. For example, DDT is still used in Mexico, although it has been limited to malaria control since 1972. However, DDT still occurs in breastmilk and some children received over 13 times the acceptable daily intake. But global trends show a downward trend in DDT concentrations in breastmilk since 1970 (Smith 1999). DDE is a derivative of DDT and may contribute to lactation failure or a shortened duration of lactation in some parts of the world where DDT and DDE are both present (Rogan 1996:63). These chemicals are not generally a problem in North America. A number of insecticides have been found in human milk. Chlordane, heplachloc, aldrin and mirex are all pesticides, some used for termite control. Chlordane was used to control cotton boll weevils and termites, and lindane was used as insecticide in Nigeria (Berlin and Kacaw 1997:77) (While revising this report, I cured an infestation of fleas and lice in my hair with a shampoo of lindane).

Dioxins and furans are by-products of many industrial processes including chlorine bleaching in pulp and paper mills, incineration of hazardous wastes, and herbicides. Dioxins refer to a family of 219 toxic chlo-rinated chemicals with varying degrees of toxicity. Two of the most hazardous are polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), formed in the manufacture of products such as insecticides, herbicides, fungicides, and wood preservatives (Guidotti and Gosselin 1999:144). Agent Orange, widely used as a herbicide in Vietnam, is one of the best known dioxins. Vietnam veterans exposed to Agent Orange have an increased risk of having children with spina bifida. The explosion of a chemical plant in 1976 in Seveso, Italy, resulted in chloracne from high doses of dioxins. Exposure is usually low level through diet, particularly from food of animal origin, rather than through industrial accidents. Human infants can be exposed to dioxins prenatally and during breastfeeding; human thyroid regulation is affected by these dioxins (Berlin and Kacew 1997:76). According to Steingraber, there is no safe dose below which dioxin causes no biological effect; dioxin tampers with human thyroid,depresses the immune system, causes birth defects and cancer, and contributes to diabetes (2001:257).

While many persistant organic pollutants are declining or leveling off, two industrial chemicals are increasingly found in the environment and in breastmilk - polybrominated diphenyl ethers (PBDEs), a class of flame retardants and aromatic amines, industrial chemicals used in the manufacture of dyes, plastic foams, pesticides and pharmaceuticals. These probable carcinogens may be recent additions to the chemical contaminants in our bodies, as they have been doubling every five years (Steingraber 2001:266).

Few reports are available on heavy metals in breastmilk and their effects on children. Although there is heavy air pollution in cities like Mexico City from gasoline lead, consequences for breastfeeding are not clear. In the United States, infant lead intoxication has been caused by infant formula or environmental sources such as lead paint and not breastmilk (Berlin and Kacew 1997:80). Lead levels in children require both medical and environmental evaluation and intervention. Less lead passes into breastmilk than across the placenta. Public health efforts aim to reduce mothers' exposure to lead. Heavy metals such as mercury, lead, arsenic, and cadmium are particular concerns in water, cow's milk, infant formulas, and particularly infant formula reconstituted with water. Mercury exposure is generally through industrial accidents and dietary exposure through seafood. In fish-eating populations in Canada, maternal ingestion of mercury-contaminated foods during pregnancy and lactation resulted in abnormal muscle tone in boys but not girls (Berlin and Kacew 1997:83). Cadmium has been reported from industrial exposure, heavy smoking, and consumption of contaminated rice, but no clear-cut cases of cadmium exposure through breastmilk have been reported, and heavy metal exposure in general is only relevant under conditions of industrial accidents.

Radioactive isotopes following exposure to radioactivity have been followed since the beginning of the nuclear age. For example, the deposition of strontium 90 in the deciduous teeth of infants in St Louis in 1964 was greater in infants fed with infant formula than those breastfed. Following the Chernobyl accident of 1986, breastmilk was found to be lower in strontium 90, radioactive iodine, and caesium than cow's milk, water, and parts of the food supply. Following Chernobyl, radioactive food imports such as infant formula, arrived in many countries, including Egypt, where government scientists tried to define safe levels of radiation (Morsey 1998:84). Since there are links between low-level fallout and immune damage, there is no safe level of exposure to radiation for anyone. Nevertheless, the risk is greater for bottle-fed infants (Lawrence 1997).

In June, 1998, world governments met to develop a treaty to eliminate persistent organic polutants (POPs). The United Nations Environment Programme (UNEP) targeted the following chemicals known as the "dirty dozen" for action; aldrin, chlordane, DDT, dieldrin, dioxins, endrin, furans, heplachlor, hexachlorobenzene, mirex, polychlorinated biphenyls (PCBs), and toxaphene. At the fifth session of the Intergovernmental Negotiating Committee (INC5) meeting in Johannesburg, South Africa in December, 2000, an internationally binding treaty to eliminate POPs was agreed upon by 122 countries. The treaty will control the production, disposal and use of the "dirty dozen". Some countries will continue to use DDT to combat malaria, pending the development of better technology. Countries will use precautionary measures to bring additional chemicals under the treaty, rather than demanding scientific proof of harm; the goal for all countries is to eliminate POPs. A network of NGOs (including WABA), the International POPs Elimination Network (IPEN), were effective lobbyists for achieving the goal of elimination and inserting strong precautionary language in the treaty. The treaty needs to be ratified by fifty countries to go into effect.

Industrial Accidents

Industrial and natural disasters have been occurring with increasing severity and frequency, signaling the failure of industrial society to "... adapt successfully to certain features of its natural and socially constructed environment in a sustainable fashion" (Oliver-Smith 1996:303). These industrial accidents provide powerful evidence of the potential of pollutants to be transmitted to humans. Many of the substances found in breastmilk following industrial accidents are substances found to cause cancer in laboratory animals. Industrial accidents are responsible for increasing the loads of contaminants in humans. In Michigan in 1974, PBBs entered the food chain after they were accidentally put in cattle feed. More than 90% of residents had measurable amounts of PBBs in their body fat and breastmilk; however, few women chose to wean their infants.
Although the long-term consequences are unclear, Michigan continues to monitor the women and children who were exposed. In Turkey in 1957 during a famine, seed wheat treated with a fungicide was consumed, killing those exposed directly and those exposed through breastmilk.

Event victims feel the immediate physical impact of industrial accidents. For example, a mass poisoning occurred in 1968 in Japan due to an industrial accident that mixed PCBs into cooking oil. Lower weight, and height in Taiwanese children was traced to PCB contaminated cooking oil. In 1976, in Seveso, Italy, a pesticide plant exploded, releasing dioxins into the air. Compared to the general population, people living nearby had three times the rate of liver cancer and other cancers were elevated (Steingraber 1997:224). In the years since the explosion, the ratio of males to females has
decreased. Among children of men who were younger than 19 when the explosion occurred, only 38% were male (Nutrition Action 2000:5). However, there was no follow-up on children who were breastfed by exposed women, and only three samples of breastmilk were analyzed. Nevertheless, exercise of political control following an accident may include orders not to breastfeed. Industrial accidents have provided much of the evidence concerning contaminants in breastmilk, although accidents tell us little about everyday contaminants in our environment.

Risks, Rights and Regulation: Communicating about Risks 
and Infant Feeding