The group of chemicals known as polychlorinated biphenyls (PCBs) were discovered in the early 20th century and used extensively in a wide range of products in the 1940s to the late 1960s. Due to potential negative human health and environmental effects, bans on PCBs being used in products started in the 1970s. Due to their non-flammability, chemical stability, high boiling point and electrical insulating properties, PCBs were used extensively in ships’ construction circa 1950s-1970s. On newer vessels, while it is still important to remain vigilant, it is increasingly becoming a rare occurrence in which PCBs are being found on board.
Exposure to PCBs containing materials to humans and the environment in and around ship recycling zones has been of particular concern in the ship recycling industry. Therefore, PCBs has been included within Table A as a mandatory inclusion in the Inventory of Hazardous Materials (IHM).
What are PCBs?
Polychlorinated biphenyl (PCBs) belong to a broad family of man-made organic chemicals known as chlorinated hydrocarbons consisting of carbon, hydrogen and chlorine atoms.
Due to their non-flammability, chemical stability, high boiling point and electrical insulating properties, PCBs were used in a number of industrial and commercial applications
Source: Wisconsin Department of Natural Resources What are PCBs?
Why is it hazardous?
PCBs have been demonstrated to cause a variety of adverse health effects. PCBs have been shown to cause cancer in animals as well as a number of serious non-cancer health effects in animals, including: effects on the immune system, reproductive system, nervous system, endocrine system and other health effects. Studies in humans support evidence for potential carcinogenic and non-carcinogenic effects of PCBs. PCBs tend to build up in living organisms both by uptake from the environment over time (bioaccumulation) and along the food chain (biomagnifaction).
PCBs are generally found in older vessels. PCB containing materials are most likely to be found in transformers and capacitors, electrical equipment including voltage regulators, switches, re-closers, bushings, and electromagnets, oil used in motors and hydraulic systems, old electrical devices or appliances containing PCB capacitors, fluorescent light ballasts, cable insulation, thermal insulation material including fiberglass, felt, foam, and cork, adhesives and tapes, oil-based paint, plastics and floor coverings
Where is it found?
PCBs is a Table A material which means it is mandatory that PCBs are included and investigated in the IHM according to the Hong Kong Convention and Ship Recycling Regulation.
A risk based approach to the investigation of PCBs should be employed due to the low likelihood of finding PCBs on newer vessels and the high cost of PCBs sample analysis. A pragmatic approach is recommended in the investigation for PCBs. During the IHM survey, conducted by a qualified IHM surveyor, a small number of indicative PCB samples should be taken from high-risk areas such as electric cabling bundles, capacitors, transformers and hydraulic oil from the steering gear. To allow for sampling without having to cut into cables, damage equipment etc., a wipe sampling approach is suggested. Due to the properties of PCBs, it is possible to detect the presence of PCBs in the surrounding area and materials next to any PCB containing material. Therefore, if PCBs are within the vicinity this will show up in the results of the wipe sample analysis and a deeper investigation will be required.
The only way to check if a material is indeed containing PCBs or not is through scientific analysis. There are 209 different congeners (forms) of PCB and it is impracticable to test for them all. The IHM Guidelines of the Hong Kong Convention suggests testing for ICES7 congeners (28, 52, 101, 118, 138, 153, 180) or the 19 congeners and seven types of aroclor mentioned in the US EPA 8082a testing method. A threshold value of 50 mg/kg is used as this is the concentration level at which wastes, substances and articles containing, consisting of or contaminated with PCB are characterised as hazardous under the Basel Convention. It is important to ensure that samples are analysed at an ISO 17025:2005 accredited laboratory to ensure accuracy and quality assurance.
The Stockholm Convention on Persistent Organic Pollutants states that from 2004 parties to the Convention can no longer produce PCBs and are obliged to stop using this chemical in manufacturing new products.
USA’s Toxic Substances Control Act (40 CFR 761)
EU’s REGULATION (EC) No 850/2004 on Persistent Organic Pollutants
Other Applicable regulations
To discuss PCBs on board, hazardous materials or any of the requirements of the IHM please feel free to get in touch with an IHM/Ship Recycling specialist via our Compliance Expert Program.