Monday, November 16, 2009


A citizen to day may be happy from the materialistic point of view getting all the comforts money can buy from thousands of innovative products churned out by technology intensive manufacturing industry. But the dangers lurking behind such a transformation during the last 5-6 decades are manifold and man's understanding of these life-threatening risks are minimal posing an uncertain future. Newer industrial chemicals developed at a frenetic pace all over the world with potential application in every day life are known to be safe to some extent though no one will guarantee100% safety. Risk benefit ratio of each new chemical ultimately decides their entry into the human chain. Continuous risk analysis has enabled the world to eliminate many of these chemicals from active use. Banning of use of halogenated hydrocarbons based on their ozone destroying property causing global warming is an example of global cooperation in such endeavors.

Food industry has its own Achilles heel in the form of chemical additives, thousands in number which are used as process aids and in packaging materials. While some of them have been cleared based on some scientific data, many are still being used under the GRAS protocol. Many of them have not been clinically tested, their safety having been assessed by only animal studies. Existence of Codex Alimentarius Commission under FAO-WHO banner provides some solace to consumers as most countries more or less follow its guidelines in the use of chemical additives. Newer analytical tools capable of detecting nanogram levels of chemicals in food and water are providing better insight into the presence of contaminants which hitherto were not considered as possible pollutants. Advent of newer and faster biological assay techniques is helping toxicologists to understand the impact of chemical substances at cellular levels. In spite of all these positive developments consumer still remains exposed to many hazards from many directions every day.

Polyfluoroalkyl chemicals (PFCs) were welcomed at one time when they were developed in 1950s, with open arms for their extraordinary ability to reduce surface tension in detergents and impart non-sticking, non-staining properties on many products. Chemicals coming under this category include Perfluorooctanoic acid (PFOA), Perfluorononanoic acid (PFNA), Perfluorooctane sulfonic acid (PFOS), Perfluorohexane sulfonic acid (PFHxS) etc and find extensive applications in many materials with which humans have contact every day. The revolutionary non-sticky cookwares, found practically in every kitchen, are made using Teflon which contains PFCs while non staining food wrappers like the ones used for take out foods and pizza delivery also have coatings based on PFCs. Most of the surfactants in use to day, lubricants,paper,textiles coatings, polishes, fire -retardant foams, carpets and many industrial products owe their special properties to the use of PFCs
during their manufacturing process. It turns out that the common house dust kicked up during cleaning the house has significant levels of PFCs which get into the blood stream through inhalation. PFCs have been detected in many water bodies and even in breast milk fed to the infants. As against 0.4 ppb of PFCs in water considered safe, there are reports indicating their presence several times this safe limit.

As PFCs can bioaccumulate and biomagnify in marine and fresh water ecosystems, the aquatic creatures are most affected causing immeasurable damage in the long run. In some countries where PFC levels are monitored periodically their concentration in blood goes up to 15 ppb but absence of more exhaustive data is worrisome because of the serious repercussions of unknown dangers that may confront the mankind in future. Some of the PFCs have a serum elimination half life of more than 8 years and they can cause lower birth weight in children, affect immune system, lead to liver damage, infertility and cancer depending on the extent of exposure. Most recently presence of PFCs has been linked to elevation of serum cholesterol, especially LDL component, in healthy individuals, though the precise mechanism is yet to be unraveled. Considering the serious health risks inherent in wide spread use of PFCs, a time has come to ban its manufacture and use through a global agreement.


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