摘要
Short-chain and medium-chain chlorinated paraffins(SCCPs/MCCPs)are of concern due to their persistence,bioaccumulation,and toxicity.SCCPs were listed in 2017 as persistent organic pollutants(POPs)in the Stockholm Convention and Rotterdam Convention for Prior Informed Consent(PIC)procedure.MCCPs are evaluated in the POPs Reviewing Committee for listing.Studies in Africa demonstrate high SCCP/MCCP levels in house dust and human milk.Therefore,this study undertook an initial assessment of the production and import situation in Nigeria.The Nigerian government has not assessed SCCPs yet and has no registered exemptions for SCCPs and therefore should not produce or use SCCPs.Also,Nigeria has not notified Rotterdam Convention of PIC procedure and,therefore,no SCCP should be imported into Nigeria.Since no local production of SCCPs/MCCPs was observed in Nigeria,this study therefore compiled data on importation of SCCPs/MCCPs and products which may likely contain these chemicals from the UN Comtrade Database for the period 1996 to 2018.Despite the listing of SCCPs in the Rotterdam Convention,there is still no specific Harmonized System(HS)codes for SCCPs/MCCPs.This study therefore used HS codes of product categories known to contain SCCPs/MCCPs.HS substance categories under which SCCP/MCCPs are usually imported include plasticisers and other product categories that amounted to 229,779 and 518,342 tonnes respectively but without specific information on the type of plasticiser.About 39%of PVC and rubber imports of 2,683,015 tonnes and 3,516,052 tonnes respectively contain plasticisers.Based on the SCCP and MCCP impact factors from literature for China,the highest amount of SCCP(33,712 tonnes)was imported in the different PVC products while rubber products accounted to 1386 tonnes and PUR foam to 2331 tonnes.The amount of imported MCCPs in PVC products(25,599 tonnes)and rubber products(32,317 tonnes)was in the same order of magnitude while MCCP imported in PUR foam was estimated to 2020 tonnes.At the end of life(EoL),these pr
