Exposure to Common Chemicals Before Birth Linked to Lower I.Q., Says Study
Two chemicals commonly found in plastics have been linked to lower I.Q.’s in children when the mothers were exposed to higher amounts of the chemicals during pregnancy, according to a new study by researchers from Columbia University’s Mailman School of Public Health.
The two compounds are di-n-butyl phthalate (DnBP) and di-isobutyl phthalate (DIBP); they belong to a class of chemicals called phthalates which are used for varied purposes, including making plastics softer and less brittle, improving spreadability of products like household paints and nail polish, and extending shelf life of scents in grooming products, household cleaning liquids, detergents and air fresheners.
Many animal studies have found that the above two and other phthalates are associated with premature birth, low birth weight, increased rate of fetal death, reduced sperm production and anatomical anomalies in male genitalia.
In humans, phthalates have been associated with physical developmental abnormalities like cleft palate and skeletal malformations; they have also been linked to DNA damage in sperm, lower sperm quality, disruption in normal activity of the male sex hormone testosterone and decreased female fertility. One recent study linked early phthalate exposure to asthma; another found an association with different health problems in teenagers, including insulin resistance.
The Columbia researchers gave I.Q. tests to 7-year-olds from 328 inner-city mothers whose urine had been tested for phthalate exposure during the third trimester of pregnancy. Researchers controlled for factors like mother’s I.Q. and education, and home environment.
Children whose mothers were in the highest quarter of exposure to DnBP and DIBP had I.Q.’s an average of 7 points lower than those of children whose mothers were in the lowest quarter of exposure.
The children of mothers with the highest phthalate levels in their systems also scored lower on processing speed, perceptual reasoning (ability to understand something not explained with words), verbal comprehension and “working” memory during the tests.
Though the study did not prove a cause-effect link between higher exposure to phthalates and diminished intellectual ability, it adds to the many studies that have given researchers reasons to think that phthalates are not as safe as once thought. Study findings were published in December, 2014 in the journal PLOS One.
Recent History of Phthalates in the U.S.
In 2009, the United States Congress banned six types of phthalates from use in baby bottles, sippy cups, items intended to be mouthed by babies, such as teething rings, and toys marketed for children under age 3.
Quite unfortunately, while exposure levels of the banned phthalates have decreased in the U.S. population, chemical manufacturers developed other phthalates that are now being used as replacements for the banned varieties in many products, and which are now being found in people’s systems. These new phthalates have been shown in animal studies to be at least as harmful as the banned types. (Source: Carrington College’s carrington.edu.)
The Environmental Protection Agency classifies phthalates as hormone disruptors.
How Can Pregnant and Nursing Moms, and Families, Protect Themselves from Exposure to Phthalates?
It’s not easy, because phthalates are so widely used in consumer goods, and they’re found in even greater quantities in the environment at large. But there are specific steps that you and your family can take, to lessen your exposure to the chemicals.
Exposure can occur via three routes: through inhalation of fumes (“off-gassing”), ingestion and absorption through skin.
To minimize absorption through skin, use as few cosmetics as possible, including baby lotions, baby powders and scented baby shampoos. Phthalates can leach from the plastic containers to the products, or they can be an ingredient in the product’s fragrance. Not all scented products have phthalates, but most do; so, it’s a good idea to choose fragrance-free cosmetics, unless you know that the fragrance is all-natural.
Also look for containers that say “phthalate-free;” some makers of natural grooming products abstain from using phthalates in their containers, but not all do. The best thing to do, to be sure, is to call the company or visit its website.
You can also visit the “Campaign for Safe Cosmetics” website, which lists many products by brand name and tells whether they have phthalates.
Families should avoid products in recyclable plastics labeled with the numbers 3, 6 or 7 at the bottom. Plastics with these numbers may leach phthalates or other dangerous chemicals.
Use fragrance-free cleaning products when possible, or make your own cleaning solutions at home. For instance, you can dilute one part non-chlorinated bleach with four parts water for an effective surface cleanser and disinfectant; substitute vinegar for the bleach, for a great glass cleaner and surface sanitizer; use a paste of baking soda and water to clean bathrooms, glass, metal fixtures, and to polish silver; use diatomaceous earth, a soft, natural, cleansing rock, as a scrubber on sinks, dishes, pots, bathtubs, toilets, etc.
To deodorize a room, try placing 20 drops of a fragrant essential oil, such as lemon or cinnamon, in a spray bottle full of water. Or place a few drops of the oil on cotton balls, and put balls on an open-window sill.
Microwave ovens are not a good idea because of the radiation they emit; but if you must use one, avoid heating foods in plastic containers, unless you know the containers are phthalate- and BPA-free (BPA, bisphenol A, is another undesirable, hormone-disrupting chemical). Better yet, use a sturdy Pyrex-type glass container to heat leftovers or fry a couple of quick eggs in a microwave oven.
Use glass and stainless steel as much as possible (glass for drinking glasses and baby bottles, stainless steel for water bottles).
Buy fresh produce if at all possible, instead of canned goods; avoid beverages sold in aluminum cans. (Nearly all tin or aluminum cans have liners that contain BPA and phthalates.) Avoid canned baby formulas; breastfeed or use powder formula, instead.
If you are making improvements to your home, be sure that any paint jobs or jobs where glues are used are well-ventilated; isolate section of the home under construction with a plastic tarp. Avoid having plastics made of vinyl in the home, such as curtains or floor tiles.
Wet-mop and vacuum often, to pick up dispersed phthalate dusts in your home.
By Eirian Hallinan