3 signs you need to switch cleaners
Your favourite soap may be too harsh on your favourite lake. Here's what to look for
While you’re singing in the shower, is your lake getting the blues? Don’t blame your vocal skills—take a look at what’s sluicing down the drain: a soapy lather of chemicals, artificial scents, algae-feeding nutrients, even germ-killing antibiotics. Not to mention the stuff you put on before you got “dirty”—sunscreen, bug dope, body spray to mask the smell of the bug dope. Blend this elixir with the slop in your septic tank, let it seep into the lake, and funny things could happen to the dockside minnows.
How funny? Combine a few parts per billion of those chemicals with the natural estrogens and androgens floating in sewage, and the result can be hormonal havoc. In extreme cases, male fish near city sewage treatment plants produce egg yolk proteins, neglect to guard their mate’s eggs, and sometimes even produce their own eggs. (Talk about getting in touch with your feminine side.)
Cottage lakes likely have less of a problem, but they may not be immune. “The impact occurs in the nearshore zone, so if you’ve got a whole bunch of cottage septic systems leaking into a sheltered bay, you might impact that zone, even if you don’t impact the whole lake,” says Mark Servos, a University of Waterloo biology professor, holder of the Canada Research Chair in Water Quality Protection, and a Lake Erie cottager. “We don’t really understand how these compounds affect the aquatic ecosystem, so we need to be very precautionary.”
Cottagers have an intimate attachment to lakes and rivers, a tie that’s both emotional and, as scientists are now learning, physical—right down to chemicals measured in parts per trillion. The good news is contamination flowing from so many minute sources can also be choked off in increments, too. Remember Vancouver’s push to cut surfactant use? University of British Columbia students found that the public appeal cut surfactant use in one neighbourhood by 16 per cent. The most toxic surfactants fell by 24 per cent—not bad for a program that only asked people to skimp on laundry detergent.
Cottagers can do the same thing, picking soaps and shampoos that reduce the stress on dockside minnows and their aquatic compatriots, and helping solve a problem where even a few nanograms per litre can make a difference.
So how to clean up when you’re cleaning up? Here’s what to look for before you hit the shower.
Warning sign 1: New antibacterial protection
When the US Geological Survey tested 85 streams between 1999 and 2000, traces of the antibacterial triclosan were found in 58 per cent of the samples. Granted, a lot of the streams were near municipal sewage treatment plants, but they also checked rural areas upstream. Given that antibacterials show up in soaps, toothpaste, and even clothing, maybe their environmental prevalence isn’t a surprise.
The problem with germ-killers is they don’t know when to quit. Even used properly, they attack the good bugs on your hands, the “permanent flora” that cling to the skin and fend off invaders. Then they rough up friendly microbes in the septic tank, and can hamper the endocrine systems of aquatic animals. Finally, there’s the problem of resistance: When bacteria get sick but don’t die, they come back meaner and stronger than ever, shrugging off antibiotic drugs when we really need them. Leave antibacterial soap for the hospital, not the cottage.
Warning sign 2: Super sudsing action
Suds, lather, and foam are brought to you by surfactants, ingredients that reduce the surface tension of water, both loosening and suspending dirt so it can be washed away. But when surfactants get into the parts-per-million range, they strip the protective mucus from fish and attack their gills. Even parts-per-billion of nonyl-phenols, breakdown products from some laundry surfactants (now restricted in Europe), can disrupt endocrine function, resulting in, among other things, male rainbow trout with stunted testicles and females that neither forage effectively nor group together to fend off predators.
To help fish keep their wits (and testes), cottagers on the soft-water lakes of the Canadian Shield can take heed of a west-coast initiative: Cut back on soap and detergent. As with Lake Muskoka or Lake of Bays, two lakes with notably soft water, Vancouver’s soft water makes more foam with less soap, so “you only need a quarter or a third of the detergent you’d need in a hard-water area,” says Albert van Rood-selaar, division manager with Metro Vancouver’s Policy and Planning Department.
Warning sign 3: New mountain fresh fragrance
Those “Alpine” scents more likely wafted in from a factory vat than the Matterhorn. In 2000, US manufacturers used 6,500 tonnes of synthetic musks in everything from soap to fabric softener. Based on samples from Lake Ontario’s Hamilton Harbour, one study estimates Hamilton-ians flush 98 mg per person per year of the common musk galaxolide into the lake. Those scents eventually settle into the lake bed. Sediment cores drawn from lakes Erie and Ontario during the ’90s and early this decade show the amount of galaxolide doubled in just eight years.
We know these artificial scents are building up in our lakes (as well as showing up in human fat tissues and breast milk) but sniffing out their environmental and health impact is more difficult. In the lab, synthetic fragrances weakened the cellular defences of mussels, and suppressed the natural estrogen production of female zebrafish.
This article was originally published on April 24, 2008