GROW-OPS MAY LEAVE HOMES UNFIT FOR LIVING

Homes that have been renovated to clean up mould and indoor air
problems caused by marijuana-growing operations may still be unfit for
habitation, says a federal researcher who will begin a study of the
problem this fall.

Fungicides, insecticides, solvents and other chemicals used in
drug-making operations are absorbed by drywall, carpeting, wood,
subfloors and concrete basement floors, said Virginia Salares, a
senior researcher with Canada Mortgage and Housing Corp. They may also
be found in backyards, where they are frequently dumped.

"People cannot take for granted it's safe," Salares said. Vapours from
chemicals can permeate the entire house, not just the rooms where the
plants were grown.

"The health risks vary depending on the concentrations of chemicals
used, how long the growing-operation was in use, and the age, immune
systems and health conditions of the people who move in.

"You wouldn't want to put an infant or a child under those conditions,
being exposed to gases," she said.

The problem has a particular resonance in British Columbia, which has
a burgeoning marijuana-growing industry.

It's hard to know the number of operations in Canada, but BC Hydro
alone estimates there are potentially 18,000 homes on its grid that
could be used for illegal purposes.

As the province with a reputation for a healthy marijuana industry,
B.C. is considered to have more than one third of all the
growing-operations in Canada. York Regional Police in Ontario have
estimated there are about 50,000 operations in Canada.

Toronto real estate lawyer Bob Aaron, who has developed some expertise
in dealing with them, says "there's tens of thousands."

Gillian Robinson, a spokeswoman for BC Hydro, said the Crown
corporation closely monitors power consumption and will give
municipalities the addresses of suspicious properties.

"We have about 18,000 homes using suspiciously high amounts of
electricity, which is often an indication of a marijuana grow-op," she
said.

The problem is also acute in Ontario, where in 2003 a police report
called Green Tide estimated there were 15,000 operations in that province.

The United Nations World Drug Report for 2005 said 40 per cent of
Canada's cannabis production is in British Columbia, with another 25
per cent in each of Quebec and Ontario.

Despite the risks, lower selling prices of former growing-operations
- -- 25 to 30 per cent less -- attract buyers looking for a deal, says
Ottawa real estate agent Richard Rutkowski, who recently represented
the seller and buyer of a former operation that had been on the market
for two years.

Robinson said BC Hydro won't reconnect a house where marijuana has
been grown until it has been inspected by an electrical inspecting
authority.

Real estate agents have to ensure everyone involved in a sale is fully
aware of the home's state, said Rutkowski. He estimates that for every
10 people interested in a property, eight will back out when they
learn it's a former growing-operation.

Other agents refuse to list them and counsel their clients to avoid
them.

"There are too many unknowns, especially with the chemicals," said
Winnipeg realtor Cindi French. "I personally would never consider them
a good deal at any price."

Salares completed a study earlier this year into mould problems and
indoor air quality in rehabilitated growing-operations. It noted that
while police succeed in identifying and seizing many of them,
marijuana growers often avoid detection by buying and selling houses
quickly.

"The homes are superficially repaired and sold to unsuspecting buyers
who may be unable to locate the previous owners," the report states.
"Where this occurs, new homebuyers can be unwittingly exposed to
hidden contaminants from damage that was cosmetically covered over
without proper remediation."

Growers typically pack hundreds of plants into small spaces with high
moisture and no natural light or air circulation. As a result, the
plants get fungal diseases and insect infestations that are treated
with high doses of chemical pesticides.

Growers are unlikely to use organic solutions or dispose of chemicals
in an approved fashion, Salares says.

If a crop spoils, they cook it to extract the drugs, and these
chemical vapours are also absorbed by the house and later released
into the air. Chemicals are often spilled on floors and poured into
soil surrounding the house, where future homeowners' children may
someday play. Chemicals are also dumped down drains.

"The plumbing of course can be flushed and cleaned, but all those
pesticides are going into the municipal sewage system or the septic
system if it's a rural house," Salares said. "All of these processes
have such harmful effects on the house, the people and the
environment."

Aaron advises buyers to insist on a clause in the purchase and sale
agreement stating the home was never used for the growth or
manufacture of illegal substances.

Salares is studying how chemicals are used in growing-operations, how
they're stored, how various surfaces absorb and give off toxic
vapours, and how a house can be rehabilitated.