Preliminary results of tests on water tanks following the HWP blaze show little cause for concern, according to Government.The level of polyaromatic hydrocarbons, a likely pollutant produced by the August fire, was said to be within “acceptable limits” after samples of water were taken from affected Pembroke homes.The full results of the tests, including those of tests for potentially toxic dioxins and furons, are not yet available.“As soon as the final report is available on dioxins and polyaromatic hydrocarbons, it will be released to the public,” said a Department of Environmental Health spokeswoman.A fire consumed the HWP building on St John’s Road on August 8, filling the area with thick grey smoke. Residents were advised to block gutters to prevent ash from entering water tanks.Drinking water samples were collected from ten homes located downwind of the fire between August 15 and August 17. The samples were then sent overseas to be tested for dioxin, furans and polycyclic aromatic hydrocarbons.“The spokeswoman said: “Preliminary results from those tests are now back and indicate that the levels of polyaromatic hydrocarbons are within acceptable limits.”Polyaromatic hydrocarbons (PAHs) occur in oil, coal and tar deposits, and are produced as byproducts of fuel burning.They vary from non-toxic to extremely toxic, with seven PAHs being linked to cancer and birth defects.Dioxins and furans, both typically produced as a by-product of industrial processes, are also toxic to varying degrees and considered likely human carcinogens.The Department of Health yesterday reminded the public that water tanks should be kept clean and well maintained.“It is a legal requirement to clean out water tanks every five years to remove sediment and to reduce the risk that it will be stirred up and ingested,” a spokeswoman said.“Sediment filters can also be fitted to ensure water quality, because the sediment is where most potentially harmful chemicals will accumulate.“Tank water that will be used to make infant formula should be boiled first to ensure it meets acceptable microbial standards.“And tanks that are sediment-free can be chlorinated using regular household bleach at a rate of 4oz for every 1,000 gallons of tank water.“Chlorine reduces microbial levels to acceptable levels. Because Chlorine dissipates, chlorination should be repeated quarterly.”