Everyday Products Expose Us To Toxic ChemicalsMar 15, 2005 | Oakland Tribune
No one can prove the link. But it's there.
It's there for Susan Liroff, diagnosed with breast cancer, who spent the 1950s on Long Island where DDT saw liberal application and the 1970s as a veterinary technician in California, bathing pets in malathion and other since-banned pesticides.
It was there for Rose Mendez, who staked a claim as one of Los Angeles' promising young architects and won a 1997 contest to redesign San Francisco's Union Square. Non-Hodgkins lymphoma snuffed that promise in 2002, killing her at age 32.
It's there for any parent watching their 3-year-old succumb to the early signs of autism.
Something in our environment is killing us.
For 50 years, society has pumped the global environment full of synthetic chemicals, reaping benefits never before imagined. And over those 50 years our bodies, almost without exception worldwide, have become repositories for those industrial and consumer chemicals.
This is our chemical "body burden. "A few years ago scientists could not even see it. Now researchers are finding some of these compounds impair our health.
They're in our environment, in our kids. They will not kill us today or tomorrow or perhaps ever, but they threaten us with insidious, almost impossible-to-detect debilities a child robbed of a few IQ points, a couple struggling to conceive.
As exposures have risen, so, too, have a string of ailments:
Breast cancer incidence rates have climbed 90 percent since 1950. Non-Hodgkins lymphoma, a cancer tied to a weakened immune system, has seen a 250 percent jump in incidence rates.
Sperm counts appear down by some indications a man born in the 1970s has three-quarters the sperm as a man born in the 1950s. Eight percent of all U.S. couples of reproductive age are infertile, according to the U.S. Department of Health and Human Services.
- And between 1982 and 1995, the number of women in their prime childbearing years to report some difficulty conceiving increased 42 percent, according to one study.
"We're all confident environmental exposures of some sort do cause cancer,''said Dr. Sheila Zahm, deputy director of the National Cancer Institute's division of cancer epidemiology and genetics. "But it's very difficult at these very low levels to know what is going on.
"We don't have good answers.''
To be sure, diet, exercise and other lifestyle choices remain by far the biggest culprit for most afflictions. In the United States, three-quarters of all new cancers can be traced to smoking, diet and obesity alone.
During the same 50-year period breast cancer rates rose 90 percent, for instance, lung cancer in women jumped 685 percent largely because women started smoking in large numbers in the 1960s and '70s.
Only in the past 10 years have scientists come to understand how exquisitely small amounts of some pollutants mimic our body's hormones, setting off cascades of largely unknown, and likely unwanted, downstream effects.
"We're not talking about retardation. We're talking about someone getting (an IQ score of) 160 instead of 170,'' said Tom McDonald, staff toxicologist at the California Department of Health's Office of Environmental Health Hazard Assessment.
In the hunt to define our body burdens' toll, scientists often fail to see the damage until after a compound is removed. Lead is such an example.
In 1975, the California Air Resources Board ordered lead out of gasoline - not over concern of lead exposure, but because catalytic converters necessary to curb smog in Los Angeles wouldn't work with the additive.
At the time, 60 ppb marked the Centers for Disease Control and Prevention health threshold. Children averaged 14 ppb.
In 1976, lead started to disappear from gasoline. By 1980, the CDC could start drawing links. Over those four years, lead levels dropped 40 percent in gasoline, 40 percent in air and 40 percent in the blood of every population cross-section the agency could track.
Since then, researchers tracking cognitive ability, memory, sensory function and motor skills in children have found dysfunction at progressively lower lead levels.
Today the average U.S. level is 2 ppb. Scientists suspect no safe level exists for children.
The central tenet of modern toxicology holds that the dose makes the poison. The amount ingested, in other words, has great say in whether a substance is a killer.
Ethanol is one example, Becker notes. Toxic at high levels, we all consume tiny amounts every day in fruits, vegetables and grains with no effect.
"You have a similar principle with reproductive toxicity,'' said Richard Becker, a senior toxicologist with the American Chemistry Council, representing chemical manufacturers. "The idea that ultra-low doses cause harm is a hypothesis. But that hypothesis generally has been shown not to hold up.''
Take perfluorinated compounds the stuff behind GoreTex, Scotchgard and Teflon. They're uncomfortably long-lasting, with a half-life the time needed for the body to purge half its total exposure of between four and eight years in humans. At high levels, they cause liver damage. The U.S. EPA sees potential for carcinogenity in the chemistry but hasn't made a definitive decision yet.
Studies suggest we all have trace amounts in our bodies, with an average of 30 ppb for PFOS, one such compound.
If that posed a problem, toxicologists reason, we'd surely see it in chemical workers at 3M's plants where blood levels average 2,000 ppb. But years of tracking data find their health no different than ours, said the company's chief medical officer.
"The low levels in the general population really do not represent a health issue,'' Dr. Larry Zobel, 3M's medical director, said. "Those levels are not associated with health effects.''
But are we looking?
University of California, Berkeley professor William Nazaroff pulls a piece of paper with a simple graph from among a sheaf of papers.
The graph shows what happens when you mix a few capfuls of Pine-Sol with water and start cleaning.
In a ventilated chamber akin to a room with an open window Nazaroff mixed a bit of vaporized cleaner with a modest bit of ozone what blows through a typical urban house on a summer day.
The result, due to a bit of reactive chemistry, was particles. An invisible cloud of hundreds upon thousands of microscopic particles still being generated four hours after the release.
That in itself is alarming. Tiny particles lodge in the lungs and are considered a key contributor to asthma. But these weren't just any particles.
They were carcinogens.
Nazaroff is one of a relatively few scientists studying the chemistry and physics of indoor air.
He looks at the ways such everyday items as carpets and air fresheners and cleaners like Pine-Sol interact, producing problematic compounds nobody expected. Given that Americans spend 90 percent of their time indoors on average, his findings are eye-popping.
Take Pine-Sol. The original formula not, for whatever reason, the lemon-scented version consists of 15 percent to 20 percent terpene. A relatively harmless hydrocarbon, terpenes are everywhere, from hand lotion to dry cleaners to air fresheners, even plants. That pine-fresh scent from Pine-Sol? The whiff of citrus from Formula 409? What you smell are terpenes.
But mix those benign cleaners with highly reactive ozone from car pollution, from an ozone-generating air cleaner, from just living in a city and that pine-fresh scent becomes far more malevolent: formaldehyde, carbonyls and other reactive and unstable compounds.
"You start with a biologically innocent compound, and you expose it to ozone, and you get a carcinogen,'' he said. "There's a lot of downside risk from reactive chemistry, as our investigations have begun to explore.''
Clorox, maker of Pine-Sol and Formula 409, notes that plant-based cleaners such as Pine-Sol have been around for 150 years or more and have played a key role improving hygiene and human health.
"Pine-Sol has never been shown to be an irritant,'' said spokeswoman Mary O'Connell. "We're not disputing there's potential for reaction, but what it means is really unclear.''