It’s unclear when thousands of British Columbians displaced by catastrophic flooding will be able to return home, but when they do, experts say there are health risks they to be aware of.
It’s a two-fold problem, stemming from both the flood water itself and the return water-damaged homes after those waters recede.
Flood waters can contain a nasty mix of harmful bacteria and biohazardous substances, including human and animal waste, mould, petroleum, and industrial chemicals, like pesticides.
Those substances can both contaminate drinking water, said Dr. Tim Takaro, and lead to infection and illness through consumption, inhalation or skin exposure.
“First of all we need to characterize better what is in all of this debris,” said Takaro, a professor of occupational and environmental health sciences at Simon Fraser University.
“We know these chemicals are out there in the environment, we know these pipelines are out there in the environment, what we don’t know is what’s in Joe’s basement at the moment.”
Municipalities may conduct tests on flood water in the days to come, but when it comes to drinking water, HealthLink BC says all private well owners should assume their wells are contaminated. Local governments, it adds, will inform those on municipal systems of the status of tap water.
This week, 48 hours of torrential rain flooded many towns and cities in southern B.C., swallowing cars, sweeping away roads, and forcing thousands to flee their homes in a hurry.
Anyone who was exposed to flood water during that process should monitor for signs of gastrointestinal illness, skin rashes and cough, said Takaro, noting that wounds, the mouth and eyes can be conduits for bacteria.
People with asthma or chronic obstructive pulmonary disease are at higher risk for respiratory exposure and should note any changes in their symptomology, he added.
“I would also be very concerned about these petroleum products because they are carcinogenic and neurotoxic and because children and pregnant women, in particular, are very susceptible to these chemicals, even at low at low exposure rates,” he said.
Takaro urged the public to take any symptoms they develop “very seriously,” even if seeking medical care seems like an inconvenience.
HealthLinkBC advises against returning home until cleanup is finished, safe drinking water is available, and proper disposal of human waste and garbage has been arranged.
Ottawa Public Health, which dealt with major floods in 2019, also recommends using basic personal protective gear at first, such as rubber boots, waterproof gloves and a facemask.
“That is a good idea, absolutely, and to have facilities to be able to wash afterwards,” said Karen Bartlett, a professor at the University of British Columbia’s School of Population and Public Health.
“All of that gets on your skin and you need to be able to wash it off, just like you wash your hands after going to the bathroom.”
All foods in homes should be thrown, said Bartlett, as should any “porous materials” that could have absorbed the flood water. That generally includes couches, carpets, pillows, mattresses, and building materials like drywall.
“If that’s wet, has been wet, and it’s not been dried out, there’s no way you can save it, just chuck it,” she said, adding that mould growth is visible within three to five days.
Exposure to mould and fungus in the home can exacerbate asthma attacks, she said, and long-term exposure can affect the immune system.
Non-porous items — like plates or surfaces that can be easily cleaned — can be kept if they’re disinfected, Bartlett explained.
“It doesn’t have to be a super-duper heavy disinfectant, even Mr. Clean or, you know, that kind of cleaning material is totally adequate to be able to wash those off.”
Returning residents should also check whether the municipality has restored power to homes, the occupational environmental hygiene professor added.
“There always is the possibility that there could be a wire or toaster underneath, and if the electricity comes back on again, there is a potential for (shock),” she explained.
“The best thing to do is make sure you know what the status of the electrical current coming into the dwelling and make sure that it’s off until everything is unplugged inside of the dwelling.”
As evacuation orders begin to lift, and residents are allowed to return home, Takaro also warned of a third health risk: mental health.
“Some people do very well with adrenaline flowing, doing what they need to do for the first 48 hours or so, but then the stress starts having its negative effects,” he explained. “That’s something that we should be very wary of as well.”
Mental health support for anyone experiencing distress during the state of emergency is available to both children and adults through the Kids Help Phone. Youth can text TALK to 686868, and adults can text WELLNESS to 741741.
For more information on what to keep and throw out, and how to sanitize your post-flood home safely, is available on the HealthLink BC website.