Rising concentrations of polybrominated diphenyl ethers (PBDEs) in Nigerian foodstuffs despite global restrictions

The presence of brominated flame retardants(BFRs)in foodstuffs of African origin is poorly understood.To fill this gap,animal-derived food samples comprising 13 different items originally from Nigeria were obtained in 2021,and concentrations of novel brominated flame retardants(NBFRs),polybrominated diphenyl ethers(PBDEs),and hexabromocyclododecane(HBCDD)were measured.Arithmetic mean concentrations of NBFRs,PBDEs,and HBCDD in Nigerian foodstuffs were 2.1 ng/g(18 ng/g lipid weight(lw)),1.3 ng/g(9.2 ng/g lw),and 0.42 ng/g(2.8 ng/g lw),with median concentrations of 1.7 ng/g(14 ng/g lw),1.1 ng/g(8.2 ng/g lw),and<0.34 ng/g(<3.3 ng/g lw),respectively.Higher concentrations of NBFRs than of PBDEs and HBCDDs in Nigerian foodstuffs likely reflect use of NBFRs as substitutes for legacy BFRs in Nigeria.Comparison with previous dietary studies reveals rising concentrations of PBDEs in Nigerian foodstuffs in recent years with associated rises in dietary exposure,possibly due to active domestic use of PBDEs in Nigeria.Reassuringly,comparison of our exposure estimates with health-based limit values suggests adverse health effects of dietary intake of BFRs by Nigerians are unlikely to occur.

Organophosphate esters in indoor and outdoor dust from Iraq:Implications for human exposure

Concentrations of 6 organophosphate esters(OPEs)were determined in 60 indoor(ID)and outdoor(OD)dust samples collected from 20 homes from Basrah,Iraq.From each home,two ID samples were collected,one from elevated surfaces(ESD)and one from the floor(FD)of the living room;while the OD samples were collected from the front yard of the same house.Total S6OPEs concentrations in dust samples ranged between 681 and 17900 ng/g with median concentrations of 5950,3590 and 1550 ng/g in ESD,FD and OD samples,respectively.Chlorinated OPEs were the most abundant compounds,contributing mean percentages of 88%,85%and 78%toΣ_(6)OPEs in ESD,FD and OD,respectively,with tris(1-chloro-2-propyl)phosphate(TCIPP)dominant.Concentrations of our target OPEs in ESD significantly exceeded those in FD(p<0.05)for tris(2-chloroethyl)phosphate(TCEP)and tris(1,3-dichloro-2-propyl)phosphate(TDCIPP).Ratios of median concentrations of OPEs in ID:OD ranged from 1.5 for tri-n-butyl phosphate(TNBP)to 8.0 for TCEP,indicating the significance of indoor sources.Concentrations of chlorinated OPEs in ID were moderately correlated(R=0.522-0.591,P<0.05)with those in OD samples,suggesting interchange of OPEs between the two environments.Concentrations of OPEs in OD from houses with a contiguous front yard car porch exceeded those in OD from houses without a car porch and were significantly higher(P<0.05)for TCEP,TCIPP and 2-ethylhexyl diphenyl phosphate(EHDPP).Emissions from parked cars and the associated home are likely sources of OPEs in the OD area.Based on the concentrations reported here,the estimated daily intake(EDI)for the Iraqi population through house dust ingestion are all well below the relevant reference dose(RfD)values.

Laboratory studies on leaching of HBCDD from building insulation foams

A series of laboratory experiments were conducted to study emissions of hexabromocyclododecane(HBCDD)into aqueous leaching fluid under simulated landfill conditions.Expanded(EPS)and extruded(XPS)polystyrene building insulation foam samples containing HBCDD were contacted with deionised Milli-Q water containing 0,100 and 1000 mg L
1 dissolved humic matter(DHM)as leaching fluid.Concentrations of HBCDD were determined in the resulting fluid and single and serial batch experiments conducted.The impacts on HBCDD concentrations in the leaching fluid temperature and pH were examined.Data from these experiments show that HBCDD concentrations in leaching fluid following contact with EPS and XPS almost all exceeded the aqueous solubilities for each diastereomer and the technical HBCDD formula.This indicates that agitation and abrasion of EPS and XPS were significant mechanisms of HBCDD emission to leaching fluid.Specifically,under such conditions,HBCDD is likely associated with fine abraded particles of the foam and concentrations in the leaching fluid are therefore not limited by the aqueous solubility of HBCDD.Consistent with this,the length of contact time had a significant positive effect on concentrations of all diastereomers in the leaching fluid for XPS and for the least soluble diastereomer,g-HBCDD for EPS.Generally,the presence of DHM in the leaching fluid and elevated leaching fluid temperatures had significant positive effects on HBCDD concentrations in leaching fluid for both EPS and XPS.Overall,while leaching fluids of pH 8.5 significantly enhanced concentrations of a-HBCDD released from EPS,pH exerts a minor effect on concentrations of HBCDD in leaching fluid.

Chlorinated organophosphate and“legacy”brominated flame retardants in UK waste soft furnishings:A preliminary study

The Furniture and Furnishings(Fire Safety)Regulations 1988 is the major driver for the use of chemical flame retardants(FRs)in soft furnishings marketed in the UK.While these regulations specify the level of flame retardancy required,they do not specify how such levels should be achieved.Consequently,it remains unclear which FRs are present in UK soft furnishings.This is important not only to help assess what FRs we may be exposed to currently,but which FRs are currently entering the waste stream with concomitant potential for release into the environment.To address this data gap,concentrations of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecane(HBCDD)and a range of chlorinated organophosphate flame retardants(OPFRs)were measured in samples of domestic and office waste soft furnishings products entering the UK waste stream in 2011 and 2012.This preliminary study measured the FR content of:carpets(n?4),curtains(n?7),mattress fabrics(n?2),furniture foam(n?9),and furniture upholstery textiles(n?10).Polybrominated diphenyl ethers(PBDEs)and hexabromocyclododecane(HBCDD)were not found at significant concentrations(below detection limits in most samples)in any of the twenty two analysed products.In contrast,7 of the 9 furniture foam samples were treated with tris(2-chloroisopropyl)phosphate(TCIPP)at a mean concentration of 1.9%w/w,with another single foam sample containing tris(1,3-dichloroisopropyl)phosphate(TDCIPP)and tris(2-chloroethyl)phosphate(TCEP)at 1.1 and 0.5%respectively.By comparison,PBDE concentrations are within the range reported previously for UK indoor dust[18],rather than the percent by weight levels required to impart flame retardancy.