Inventory approach for short-chain chlorinated paraffins for the Stockholm Convention implementation in Brazil.

Chlorinated paraffins (CPs) are chemicals with multipurpose applications. Their global production has increased despite their adverse impacts on the environment and human health. In 2017, short-chain chlorinated paraffins (SCCPs) were listed as persistent organic pollutants (POPs) in the Stockholm Convention. Yet, specific exemptions were granted for their applications despite the recycling prohibition for products containing SCCPs. Therefore, we aimed to produce the first Brazilian inventory of SCCPs following its respective guidance to evaluate the applicability of the SCCP inventory guidance and to provide technical insights regarding SCCPs in the update of the Brazilian National Implementation Plan (NIP). Moreover, we performed a review of SCCP occurrence in Brazil to fulfil data gaps in the inventory development. We identified and consulted nationwide stakeholders and assessed foreign trade data of CPs and products that might contain CPs in relevant amounts. The Brazilian production of CPs was discontinued in 1994. However, CPs are still imported and used in the country. CPs have been mostly applied as plasticizers, flame retardants and lubricants in Brazil. The import of products containing CPs also pose a significant route of CP entrance into Brazil. Thus, the current end-of-life management of CP-containing products is a bottleneck towards the Convention implementation. The guidance application was feasible and useful despite the low engagement of stakeholders. To assess foreign trade of CPs and CP-containing products, we recommend the use of more specific tracking codes. Besides, the review of SCCP occurrence is not a demanded part for an inventory but was a useful complementation.

Material and Substance Flow Analysis of Used Lead Acid Batteries in Nigeria: Implications for Recovery and Environmental Quality.

BACKGROUND: As resources become scarce, information from material and substance flow analysis can help to improve material recovery policy. The flow of toxic substances such as lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As) and antimony (Sb) can be used as a basis for appropriate risk management decisions for optimum environmental quality. OBJECTIVES: The present study examined a material and substance flow analysis of used lead acid batteries (ULAB) from motor vehicles and implications for environmental quality in Nigeria. METHODS: Information on motor vehicle imports was obtained from the literature. Mathematical models were constructed and used for the material and substance flow analysis. Samples of 50 brands of ULAB pastes were digested using a microwave digestion system followed by elemental determination (Pb, Cd, silver (Ag), As, cobalt (Co), calcium (Ca), Cr, copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), Sb, selenium (Se), and tellurium (Te)) with inductively coupled plasma optical emission spectroscopy. RESULTS: Approximately 4.8 million tons (Mt) lead acid batteries (LAB) from vehicles was used in Nigeria between 1980 and 2014, out of which approximately 2.6 Mt had reached end-of-life (EoL) stages. From the total amount in EoL, approximately 2.3 Mt was recycled, and 0.3 Mt was landfilled. Among the toxic elements, Pb, Cd and As were the most abundant in ULAB; and of the valuable elements, Fe and Cu had the highest levels. Approximately 3.5 Mt of Pb was used in the past (1980-2014) in ULAB for motor vehicles, out of which approximately 1.9 Mt tons was in EoL stages. DISCUSSION: The results revealed that the battery pastes were heterogeneous. Only Pb exceeded the total threshold limit concentration (TTLC) of 1000 mg/kg. The TTLC describes the safe levels or concentration of heavy metals in the environment. The levels observed for other metals in this study were below the TTLC values. The present study estimated an average life span for lead acid batteries in motor vehicles in Nigeria of 5 years, suggesting an additional 2.2 Mt at EoL by 2019. High concentrations of Pb in air, water and soil carry the potential for contamination of food products, especially in Nigeria, where food is traditionally prepared and sold in open air markets in an unregulated manner. CONCLUSIONS: High amounts of toxic elements present in the various life cycle stages signal potential environmental and human health hazards. COMPETING INTERESTS: The authors declare no competing financial interests.

Concentration and Distribution of Organochlorine Pesticides in Sediments of the Niger River, Nigeria.

BACKGROUND: Pollution in aquatic ecosystems is a serious environmental concern. There is a great need for constant assessment and monitoring of hazardous substances, particularly in aquatic environments in developing countries, as rivers are media with easy trans-boundary transport of chemical substances. OBJECTIVES: The present study assessed the occurrence and distribution of organochlorine pesticides (OCPs) in the sediments of the Niger River, Nigeria. METHODS: A total of 120 samples of sediment were collected from 15 locations along the river using Van Veen grab. The Environmental Protection Agency (USEPA) 3570 method with slight modification was used for sample preparation. Organochlorine pesticides were analyzed using Hewlett Packard 5890 series II gas chromatography with electron capture detector. Confirmation of OCPs was performed using a gas chromatograph/mass spectrometer (Shimadzu QP2010) and capillary column type HP1MS (30 m × 0.25 um × 0.25 mm id). RESULTS: The highest concentration of ∑OCPs in the sediment samples of the River Niger (5023±1596 µg/kg, 4672-7009 µg/kg) was detected in a location at Onitsha, while the lowest concentration (1570±204.5, 1214-1820 µg/kg) was detected in a location at the Nicolas River. DISCUSSION: High values of ∑OCPs (>2000 µg/kg) were detected in all of the locations except in three locations where lower levels were detected. The ∑OCPs were higher during the dry season compared to the rainy season. This may be because the resident time of the sediment transported was higher during the dry season compared to the rainy season, which is characterized by storms, high current, and bottom scour. The chlordane concentration ranged between 24.4 and 134.1 µg/kg dry weight (dw) in locations Nicolas 14 and Lokoja 5; and the Probable Effect Concentration guidelines were exceeded. Dieldrin was detected at very low levels in most of the locations and ranged from 5.67 to 70.3 µg/kg dw in locations Onitsha 9 and 8; and the Probable Effect Concentration guideline was only exceeded in location Onitsha 8; however, the Toxic Effect Concentration guideline was exceeded at all of the locations. Dichlorodiphenyldichloroethane (DDD) was not detected in location Lokoja 6 or 7, and Onitsha 8 and 9, although the concentration in all other locations exceeded the guidelines. Dichlorodiphenyldichloroethylene (DDE) concentrations exceeded the guidelines except in location Nicolas 13. CONCLUSIONS: Due to the environmental/human risk and potential danger of the elevated levels of OCPs, there is a need for continuous monitoring of the Niger River. COMPETING INTERESTS: The authors declare no competing financial interests.

Polychlorinated Biphenyls in Brackish Water Fish in the River Niger, Nigeria.

BACKGROUND: Anthropogenic polychlorinated biphenyls (PCBs) in aquatic environments poses human and ecological health risks in Nigeria. OBJECTIVES: This study determined the concentrations of PCBs in brackish water fish in the River Niger to assess the contamination status of fish consumed by the local population. METHODS: The sampled fish species included Drepane africana, Mochokus niloticus, Chrysichthys nigrodigitatus, Pristipoma jubelini, Vomer septapinis, Pseudotolithus senegalensis, Mugil cephalus, Pseudotolithus elongatus, Sphyraena piscatorum and Lutjanus goreensis, purchased from landing sites. Six fish from each species were sampled, for a total of 60 samples. Twenty-seven (27) PCB congeners, #8, #18 #28, #44, #52, #60, #77, #81, #101, #105, #114, #118, #123, #126, #128, #138, #153, #156, #157, #167, #169, #170, #180, #185, #189, #195, and #206 were screened in the fish samples using standard methods. The PCBs were identified and quantified using gas chromatography (GC) (Hewlett Packard GC 5890 series 11 with electron capture detector). Confirmation was performed using Shimadzu GCMS QP2010. RESULTS: The sum of the National Oceanic and Atmospheric Administration Agency (ΣNOAA) PCBs occurred at the highest concentration of 1830.0±484.0 µg/kg detected in Vomer septapinis, and the lowest in Pseudotolithus senegalensis, with a mean concentration of 795±169.3 µg/kg. The concentration of dioxin-like (DL) PCBs was highest in Pristipoma jubelini (992.0±88.6 µg/kg) and lowest (285.6±81.5 µg/kg) in Drepane africana. The highest mean concentration (418.±177.6 µg/kg) of International Council for the Exploration of the Seas-7 (ICES-7) PCBs was observed in Vomer septapinis. The heavier ICES-7 congeners PCB-138, PCB-153, and PCB-180 occurred at higher concentrations compared to the lighter molecular weight ICES-7: PCB-28, PCB-52, and PCB-101. The European Union (EU) marker PCB limit of 335 µg/kg was exceeded in all the brackish water fishes with the exception of Mochokus niloticus, Pristipoma jubelini and Pseudotolithus senegalensis. DISCUSSION: The total level of PCBs in the brackish fish samples was relatively high at >1000 µg/kg (above the World Health Organization (WHO) and Food and Agriculture Organization of the United Nations (FAO) guideline of 1000 µg/kg fresh weight). The EU guideline value for fish (220 µg/kg fresh weight) was exceeded in about 80% of the brackish fish samples studied. CONCLUSIONS: Consumption of fish from the River Niger may expose humans to polychlorinated biphenyls. In addition, since contamination of the fish samples is an indication of river contamination, river water quality is of great concern and there is a need for additional PCB data on water quality to be distributed to the community, followed by mitigation measures. COMPETING INTERESTS: The authors declare no competing financial interests.

Initial Inventory of Plastics Imports in Nigeria as a Basis for More Sustainable Management Policies.

BACKGROUND: Plastic is a waste stream with recycling and recovery potential. However, the recycling rates for plastic in African countries are low. Furthermore, use and production of virgin plastics are increasing. Therefore, a high proportion of plastic waste is being disposed of in landfills and dumpsites. Plastic serves as fuel for open burning at landfills/dumpsites with associated releases and constitutes a large fraction of marine litter, making it a major and growing global pollution concern. OBJECTIVES: This study aims to develop an initial inventory of plastics in Nigeria towards the development of an effective plastics management frame. METHODS: A search was conducted of the recent literature and the United Nations (UN) Comtrade database using harmonized system (HS) codes for import data of various polymer categories and major product categories containing plastic. Algebraic expressions were developed for calculation of the share of plastic in these products. RESULTS: Approximately 14,200,000 tons of plastics in primary form were imported into Nigeria between 1996-2014. Approximately 3,420,000 tons total plastic were imported in the form of products and approximately 5,545,700 tons were imported as product components. Approximately 194,000 tons of plastic toys were imported over a six-year period. DISCUSSION: The total amount of plastics imported in primary form and as products equals 17,620,000 tons. The total volume of imported plastic, newly produced plastic and plastic components going into the technosphere was 23,400,000 tons. The huge amount of plastic and other polymers entering the technosphere in Nigeria has important implications for marine litter, pollution, waste management and resource recovery. CONCLUSIONS: A huge volume of plastics has entered the Nigerian technosphere, with less than 12% of the resulting waste entering the recycling stream. There is a need for sustainable management of this crucial waste and resource category. Potential mitigating strategies include waste plastic reuse, recycling, waste conversion to energy, and appropriate plastic control policy frameworks. COMPETING INTERESTS: The authors declare no competing financial interests.

Levels of Organochlorine Pesticides in Brackish Water Fish from Niger River, Nigeria.

Investigation of the levels of organochlorine pesticides (OCPs) in fish samples was carried out to assess the contamination status of Niger River. Ten different brackish water species of fish (6 samples for each, making a total of 60) were purchased from landing sites at the Delta area of Niger River. These were Drapane africana, Mochokus niloticus, Chrysichthys nigrodigitatus, Pristipoma jubelini, Vomer septapinis, Pseudotolithus senegalensis, Mugil cephalus, Pseudotolithus elongatus, Sphyraena piscatorum, and Lutjanus goreensis. OCPs were determined using standard methods. Certified reference standards from Accustandard USA were used for the instrument calibration and quantification of OCPs. Twenty OCPs, namely, α-HCH, ß-HCH, γ-HCH, δ-HCH, endrin, endrin aldehyde, endrin ketone, heptachlor, heptachlor epoxide, aldrin, dieldrin, endosulfan I, endosulfan II, endosulfan sulfate, methoxychlor, α-chlordane, γ-chlordane, DDE, DDT, and DDT, were identified/quantified using Gas Chromatography (GC) (Hewlett Packard GC 5890 series 11 with electron capture detector). Confirmation was done using Shimadzu GCMS QP2010. The highest concentration of ∑OCPs in the brackish fish samples of the Niger River, 4302±2066 µg/kg fresh weight, with a range of 2237-6368 µg/kg, was detected in Drapane africana, while the lowest concentration, 2320±876.4, with a range of 1006-3288 µg/kg, was found in Mochokus niloticus. The concentration of total OCP compounds varied markedly amongst the different fish species. The guideline value of 2000 µg/kg fresh weight by WHO/FAO was exceeded and therefore implied potential harmful effects on humans. Since contamination of the fish samples was an indication of contamination of the river, the quality of the water for public water supply should be of concern; and therefore further monitoring is suggested.

Polybrominated diphenyl ethers listed as Stockholm Convention POPs, other brominated flame retardants and heavy metals in e-waste polymers in Nigeria.

Polybrominated diphenyl ethers (PBDEs) were the first brominated persistent organic pollutants (POPs) listed in the Stockholm Convention. Parties to the convention are currently establishing inventories for developing action plans for the environmentally sound management of PBDE-containing materials. The major use of commercial octabromodiphenyl ether (c-OctaBDE) has been in casings from cathode ray tube (CRT) TVs and computer monitors. Large quantities of used e-waste and electronic equipment have been exported to developing countries with Nigeria being a major importer in Africa. The casings from 382 TVs and computers imported from major world regions to Nigeria were sampled in backyards and waste dumps. The samples were screened with X-ray flourescence (XRF) for bromine and analysed by gas chromatography/ electron capture detection (GC/ECD) for brominated flame retardants (BFRs). A high proportion of the CRT casings (61 %) contained more than 10,000 ppm bromine from BFRs. Decabromodiphenyl ether (DecaBDE) was the major flame retardant used in TV sets and tetrabromobisphenol A (TBBPA) for computer CRTs.The screening suggests that average PBDE levels (of c-OctaBDE + DecaBDE) in Nigerian-stockpiled CRT casings were 1.1 % for TV and 0.13 % for PC CRTs. These are above the Restriction of Hazardous Substances (RoHS) limit and should be separated for RoHS compliant recycling. The Nigerian e-waste inventory of 237,000 t of CRT plastic would therefore contain approx. 594 t c-OctaBDE and 1,880 t of DecaBDE. In Nigeria, as for most developing countries, there is currently no adequate e-waste management, plastic separation or destruction capacity. The data highlight the urgent need to develop environmentally sound management for this large material flow.

Substance flow analysis of polybrominated diphenyl ethers in plastic from EEE/WEEE in Nigeria in the frame of Stockholm Convention as a basis for policy advice.

This study investigated the material/substance flow of polybrominated diphenyl ethers listed in the Stockholm Convention (SC) as persistent organic pollutant (POP-PBDEs) in the most relevant plastic fractions in Nigeria. Considering the prohibition of production and the use of POP-PBDEs and knowing that these pollutants are still contained in electrical and electronic equipment (EEE) and associated wastes (WEEE), it is necessary to determine their flows, especially in developing countries with limited end-of-life management. Following the inventory approach of the SC Guidance and utilizing the existing national e-waste inventory together with monitoring data, a material/substance flow analysis was conducted using the STAN tool. Within the period of 2000 to 2010, the total import for EEE/WEEE in Category 3 and 4 was approximately 8 million tonnes (Mt) containing approximately 2.4 Mt of polymers. For the inventory year 2010, it was estimated that from these polymers, about 0.8 Mt was still in stock and 1.6 Mt has reached the end-of-life. It was also estimated that approximately 1.1 Mt has ended in dumpsites, 0.3 Mt was burned in the open, and 0.2 Mt was recycled. In the plastic fractions, 1,270 t of POP-PBDEs was contained with about 370 t still in use/stock and approximately 900 t has entered the end-of-life phase. All three major end-of-life treatments result in environmental pollution with associated exposure risk. The implementation of the Stockholm Convention represents an important opportunity to improve this management situation in Nigeria and other developing countries.