No one has ever taken a vacation who took along a baby. You can go out of town with a baby, you can even leave the country or be on the lam with a baby, but you are never on vacation. Mothers who don’t breast-feed usually leave baby with dad or a sitter when they go out of town, but a nursing mother hasn’t any choice. A bottle-fed baby is inseparable only from the nearest supermarket, but a breast-fed baby is inseparable from the breast.
Many women find it easier to keep themselves on hand than to keep the pantry stocked with infant formula. I do. And more and more women are now aware that artificial formula can’t substitute for human milk. Mother’s milk is a great natural resource: it’s in endless supply in a healthy mother, it’s always the right temperature, it costs less than a thousand calories a day to manufacture and absolutely nothing to deliver, and it’s almost always perfectly suited to the consumer.
There is only one flaw in this otherwise ideal consumer product: it is vulnerable to contamination. And because of that, I took a trip—not a vacation—with my four-month-old nursing baby to a pesticides laboratory in South Texas to find out if my milk contains something it shouldn’t. Nothing less could have prodded me to travel with a baby.
The Human Milk Study has thirteen laboratories across the country, one of them in Texas. The study, the second of its kind (the first was done in 1975-76), is monitoring the incidence of seventeen substances—sixteen pesticides and one industrial pollutant ( PCB)—in mother’s milk samples across the nation. The study’s purpose is to identify any pesticides that might be approaching dangerously high levels. The labs do not take unsolicited samples as part of this study, but the Texas lab, under the guidelines of another of its projects, works with people who suspect they have a pesticide problem. Since they are equipped to analyze milk, they accepted my sample. They could tell me what I wanted to know: did my milk have high levels of pesticides?
What I had read recently led me to believe that even I, a fastidious consumer of health food and a confessed coward when it comes to handling so much as a can of Raid, might have picked up some pesticides and that my nursing son might be taking in chemicals that could cause him to develop cancer or some undiagnosable organic or behavioral disorder. A 1950 test showed that 24 women who occasionally used DDT sprays had residues in their milk ranging from zero to 770 parts per billion. (The World Health Organization has recommended 50 ppb as the maximum safe level of total DDT concentration in cow’s milk.) A 1971 test of people in rural Colorado found levels of two DDT derivatives that ranged from 19 to 386 ppb and from 7 to 109 ppb, and a 1972 test from South Carolina found three DDT derivatives almost universally in those tested (it also found high amounts of dieldrin and PCBs). DDT, which was first used in 1936, was banned by the Environmental Protection Agency ( EPA) in 1972; however, it is a “persistent” pesticide—a polite way of saying it will be around for a long time.
The report that struck closest to home was made by Patrick O’Keefe, a Harvard chemist working on an EPA-funded project in 1976. O’Keefe was concerned with rangelands, including some in West Texas, that were being sprayed with 2,4,5-T, the defoliant containing dioxin, which is similar to the notorious Agent Orange used in Viet Nam. Dioxin is such a poisonous substance that its toxicity is measured in parts per trillion. O’Keefe found that half the milk samples he took from mothers in San Angelo contained between 0.5 and 1 part per trillion. Safe levels for dioxin in humans have yet to be established, but the chemical is suspected of having caused miscarriages in women in Oregon forest areas sprayed heavily with 2,4,5-T. On the basis of these miscarriages, the EPA imposed an unprecedented ban on 2,4,5-T this year—a sort of “guilty until proven innocent” sentence. However, exemptions to the ban include spraying on rangelands and rice fields, which means 900,000 acres of Texas farm and ranch land will continue to receive seasonal doses of 2,4,5-T.
The Texas Tech School of Medicine’s pesticides laboratory is in San Benito in the Valley, an area whose rural landscape belies a history of heavy, sophisticated pesticide applications to cotton and food crops. The EPA contracted with the lab to participate in the Human Milk Study. Because the pesticides they are looking for—chlorinated hydrocarbons and organophosphates—are lipid (fat) soluble, milk is used for analysis. It is easily available for study but it is not a perfect test vehicle, because it restricts the testing to women and the fat content of milk varies throughout the day and during a feeding.
A larger problem with the study is that it tests for so few substances. Approximately two thousand compounds compose an EPA list of restricted chemicals, of which thirty are pesticides; there are about fifty substances suspended or severely restricted because they are known or suspected carcinogens. All the pesticides, or their derivatives, under investigation in the Milk Study come from one or the other list. In addition to these pesticides, the study is looking for PCBs (polychlorinated biphenyls), a wide-spread industrial pollutant used in transformers, brake fluid, and capacitors, among other things, that has entered the ecosystem through dumping into water supplies.
A friend, also a nursing mother, endured the flight to the Valley with baby and me; this was her first vacation from her daughter, whom she hoped to wean by a gently enforced separation. We were a motherly crew, eating supper at Sambo’s in Harlingen. Discreetly nursing baby Jeff, I tried with one hand to construct and hold together a cheeseburger. Sue Ellen’s chef’s salad somehow failed to live up to my idea of a Rio Grande Valley chef’s