PCB’s- Industrial Breakthrough, Environmental Pitfall

Polychlorinated biphenyls commonly known as PCBs are man made chemicals that never existed in nature prior to their invention in early 1900’s and widely released into the environment by the manufacturing sector and consumers. The growing popularity of PCBs were attributed to its low degree of reactivity. They are not flammable, have high electrical resistance, good insulating properties and are very stable even when exposed to heat and pressure. Their primary use, however, was as a dielectric fluid in electrical equipment. Because of their stability and resistance to thermal breakdown as well as their insulating properties they were the fluid of choice for transformers and capacitors. As a matter of fact, because of their fire resistance, they were required by some fire codes.

During the 1970's, the health risks associated with PCB's became a major consideration due to several well publicized incidents. The most noted of these is known as the Yusho Incident. It took place in Japan when a rice oil plant had an equipment leak of PCB fluid into the product. The rice oil was sold and consumed resulting in many people being adversely affected.

Among the health affects of PCB's are skin ailments called chloracne, reproductive disorders, liver disease and others. PCB's are a suspected human carcinogen and a known animal carcinogen. They are resistant to degradation and therefore persist for many years in the environment. Furthermore, they bioaccumulate in the foodchain and are stored in the body fat of animals and humans.

Biodegradability is related to the amount of chlorination of a specific PCB. The higher the chlorine content of a PCB, the less the biodegradability. The lack of degradability of PCB compounds results in bioaccumulation of PCB’s in the environment.

Methods of destruction

Landfill –Many municipal sites are not designed to contain these pollutants and PCBs are able to escape into the atmosphere or ground water.

Ultrasound – In a similar process to combustion, high power ultrasonic waves are applied to water, generating cavitation bubbles. These then implode or fragment, creating microregions of extreme pressures and temperatures where the PCBs are destroyed.

Incineration – Although PCBs do not themselves ignite, they can be combusted under extreme and carefully controlled conditions. Current regulations require that PCBs are burnt at a temperature of 1200ºC for at least two seconds, in the presence of fuel oil and excess oxygen.

Microbial – Much recent work has centred on the study of micro-organisms that are able to decompose PCBs. Generally, these organisms work in one of two ways: either they use the PCB as a carbon source, or destruction takes place through reductive dechlorination, with the replacement of chlorine with hydrogen on the biphenyl skeleton.

Chemical –Many chemical methods are available to destroy or reduce the toxicity of PCBs.Aromatic nucleophilic substitution is a method of destroying low concentration PCB mixtures in oils, such as transformer oil. Substitution of chlrorine by poly(ethylene glycols) occurs in under two hours under a blanket of nitrogen, to prevent oxidation of the oil, to produce aryl polyglycols, which are insoluble in the oil and precipitate out.

New Facility

	Excitement and anticipation continues to build as our move in date into the new 12th Street Environmental Centre approaches. Our administration areas are now complete with beautiful flooring and new office furniture. We are especially proud of our front reception area that brings a warm contemporary feel to our front office. Our IT and phone networks have been installed and our Oracle LIMS database, servers, email, and citrix capabilities tested.
	Substantial progress has been made to the lab areas with all air exchange and exhaust systems installed and a good portion of the benching now in place. The painting is complete and electrical work nearing completion. With the labs and logistics area now taking shape, we anticipate our move sometime in mid summer. We will keep all our clients posted as to when they will be able to drop off samples at our new 2910 Street location. This promises to be an exciting summer as we gear up for the move and meet the challenges of a fast growing AGAT. Please feel free to contact your Client Service or Business Development Representative for a sneak peek tour of the new state of the art Environmental Laboratory.
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AGAT Spotlight

Maria Catalfamo BSc.Chemistry, Client Services Supervisor

This month we focus on an integral position within the AGAT family, the Client Service Representative. In Calgary, Maria Catalfamo exemplifies the service driven qualities our clients have come to expect from us. She project manages accounts and strives to add a personal touch to the work she performs. Maria provides a link to the laboratory for our clients by efficiently handling client queries so that they get the answers they need when they need it. She attained her BSc. Chemistry from the University of British Columbia and has had several years experience working in Chemical processing markets for both Marsulex Inc and Chemtrade Logistics before joining AGAT. She shows a distinct drive to excel in her role often going the extra mile by promoting AGAT in conjunction with the business development team and puts in the extra hours to surpass client expectations. We are glad to have her as part of our Environmental team and know that clients will be impressed whether she is managing their accounts or meeting her in person.

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