Chemical odours coming from a building or exhaust fans in an unusual location, and running for long periods and at odd times, are external indications a property may be being used to cook methamphetamine.

These detection tips come as Police say the number of homes contaminated by P is on the rise in the Western Bay of Plenty.

Signs a home has or is being used to cook methamphetamine include chemical odours and external exhaust fans in unusual locations.

In 2012, police busted seven methamphetamine labs in Tauranga, two in Mount Maunganui, one in Katikati and one in Te Puke.

New Zealand Drug Detection Agency Bay of Plenty general manager Leigh Sefton says there are a number of things people can look for to indicate if a methamphetamine lab is or was once operational in a house.

Frequent visitors to the address at odd hours, blacked out windows, or curtains drawn permanently are other signs, says Leigh.

'Unfriendly occupants, secretive about their activities, and paranoid or odd behaviour, expensive security and surveillance equipment around the property, access denied or restricted to landlords, neighbours or other visitors, rubbish containing cold and flu remedy boxes, chemical containers, bottles and boxes with labels removed [are other signs].”

Leigh says when people are watching for signs of a methamphetamine lab inside a home they should look out for containers filled with clear liquid and chalky-coloured solids on the bottom.

'Containers with double-layered liquids in them, used coffee filters coated with white pasty or reddish brown substance, baking dishes or similar containing white crystalline powder or substances, or yellowish-brown staining on the walls or ceiling are all indications P is either being cooked or was once cooked in a house or property.”

Health risks caused by exposure to P lab chemicals depend on the manufacturing process and chemicals being used, the amount of chemical and length of exposure, and the age and health of the person exposed.

Leigh says chemicals may enter the body by being inhaled, ingested, or absorbed through the skin.

An acute exposure is one that occurs during a relatively short period of time. Acute exposure to meth lab chemicals can cause shortness of breath, cough, chest pain, dizziness, lack of coordination, chemical irritation, or burns to the skin, eyes, nose and mouth.

'Death could result when exposure is to a particularly toxic chemical or the person exposed is particularly vulnerable,” says Leigh.

'Phosphine is by far the most deadly hazard at Clan Labs [clandestine labs]. Overseas, two separate instances have been documented where Clan Lab ‘cookers' were found dead at the scene and their deaths were attributed to phosphine over-exposure. Phosphine gas is a by-product of the reaction, and is given off by red phosphorus itself in small quantities.”

Leigh says the best way for potential home owners to avoid any of these worries is to get a pre-purchase inspection done, including getting the property tested for methamphetamine.

'The scope of this type of testing will largely depend on what you want to know with regard to the property having been used as a clandestine drug laboratory to manufacture methamphetamine, or if it has been owned or tenanted by drug users who have smoked methamphetamine in the property.

'This testing will identify if the property has a level of methamphetamine residue present above Ministry of Health's draft guidelines. If it does then further testing is recommended to establish if the level of contamination is likely to have been caused by the manufacture of methamphetamine or the illegal use of the drug.”

Leigh says the rooms or areas to be tested can be selected by the owner or landlord, or by the experienced NZDDA staff, who can advise on the best rooms or areas to test with respect to where clandestine drug laboratories are usually found or where smoking of the drug generally takes place.

'At the completion of the testing we'll advise our client of the results immediately and will receive a report outlining the following: the areas tested, the result of the tests, photographs,” says Leigh.

'Any recommendations with respect to having the property cleaned, the likely cause of the contamination; and should any of those tests indicate the presence of methamphetamine, it is recommended that a laboratory-based company be involved and a full lab work-up of the property be done to establish the extent of the contamination.”

For more information about meth detection services visit: www.nzdda.co.nz/