Inventory and substance flow analysis of polybrominated diphenyl ethers in the Nigerian transport sector—end-of-life vehicles policy and management

Abstract

Recently, certain polybrominated diphenyl ethers (PBDEs) have been listed as persistent organic pollutants (POPs) in the Stockholm Convention. In this study, a preliminary material and substance flow analysis of commercial pentabromodiphenyl ether (c-PentaBDE) was conducted for motor vehicles-a major use sector for POP-PBDE in polyurethane (PUR) foam-for Nigeria. The methodology of the Stockholm Convention PBDE inventory guidance was used for the calculation of c-PentaBDE. Material/substance flow analysis was conducted applying the STAN software. The time frame for this analysis was 1980-2010, considering that this was the period when POP-PBDE-containing vehicles were largely imported into Nigeria.It is estimated that the approximately 19 million passenger cars imported from 1980 to 2010 contained ca. 270 t of POP-PBDEs in ca. 401,000 t of PUR foam. A major share of cars from the USA and only a small share of cars from Europe and Asia were impacted. This simplified material and substance flow of PUR foams and POP-PBDEs in motor vehicles demonstrated the potential for environmental/human contamination and pollution of recycling/reuse for Nigeria and other developing countries.The study developed the first preliminary inventory of end-of-life vehicles for Nigeria, following which the environment ministry has taken up the important issue of end-of-life vehicles management. Considering that a range of other pollutants are contained in vehicles (e.g. heavy metals, flame retardants, PCBs, chlorofluorocarbons, hydrofluorocarbons and waste oil), this initiated activity should finally lead to an integrated management of pollutants and resources from the transport sector.

Current Levels and Management of Solid Wastes in Nigeria

“…The import of motor vehicles into African countries has increased exponentially. Between the years 1980 and 2010, estimates indicate that approximately 19 million motor vehicles were said to have been registered in Nigeria, of which 4 million reached end‐of‐life status in the last three decades (Babayemi et al., , Babayemi, Osibanjo, Sindiku, & Weber ). Considering the trends in the growth of the world's transport fleet, which increased globally from 100 million in 1960 to 800 million in 2002, it has been estimated that the number of motor vehicles currently in use will double in the next 25 years (Harrington & McConnell, ).…”

“…The estimated 19 million motor vehicles registered in Nigeria between 1980 and 2010 contained approximately 410,000 t of PUR foam. Of this amount, 84,000 t PUR foam was contained in EoL motor vehicles (Babayemi et al., , ). Although there are instances of dismantling and recovery activities for motor vehicle components, there is no effective management of PUR wastes in Nigeria (Agbo, , ).…”

“…Although there are instances of dismantling and recovery activities for motor vehicle components, there is no effective management of PUR wastes in Nigeria (Agbo, , ). EoL motor vehicles are still abandoned at accident sites, road sides, garages, backyards, and auto‐mechanic villages (Agbo, ; Babayemi et al., ), where they rust away, and deface and pollute the environment in addition to constituting a loss of precious resources that could be used to grow the Nigerian economy.…”

“…Globally, it was estimated that 7 Mt of scrap tires were generated yearly (Hita et al., ). Also, considering the Nigerian case (Babayemi et al., , ), the estimated 19 million motor vehicles registered between 1980 and 2010 would contain 76 million tires, without considering spare tires and the amount replaced during the lifetimes of the vehicles. It is obvious that huge amounts of tires (including those from bicycles, motorcycles, and tricycles) have entered the waste stream in the last three‐and‐a‐half decades.…”

Waste prevention for sustainable resource and waste management

“…Although the Pb content per vehicle was successfully reduced by up to 100 g-Pb, it was pointed out that it will take some time for this reduction to influence the Pb content in ELVs and ASR [48]. The toxic chemicals, such as brominated flame retardants (BFRs), that are contained in ELVs have also become global concerns [106,108]. In addition to their levels of toxicity, the need to develop resource recovery methods has become more important because electric devices and next-generation vehicles (such as HEVs and EVs) are becoming increasingly popular.…”