Diet and indoor environments as predictors of human body burden of PBDE

自20世纪70年代以来，要求在软家具和电子产品中添加阻燃剂的立法拯救了许多人的生命。溴化阻燃剂(BFR)包括多溴联苯醚(PBDEs)，它广泛存在于环境中并具有生物累积性。《斯德哥尔摩公约》(2004年)要求签署国减少或消除无意和故意产生的持久性有机污染物的排放，以保护人类健康和环境。新出现的持久性有机污染物，如多溴二苯醚，可能很快就会被列入“肮脏的十几个”名单中。人们对多溴二苯醚的大小和暴露途径知之甚少。它们在制造、回收和焚烧过程中释放，可以从处理过的材料中浸出到大气中，并可以通过皮肤接触吸收。在过去的30年里，多溴联苯醚的人体负担每五年增加一倍。多溴二苯醚是亲脂性的，在人体脂肪组织中积累。母婴传播发生在母乳喂养期间。众所周知，幼儿花时间在地毯上，并经常表现出手对嘴的行为会增加身体负担。接触持久性有机污染物的另一种途径是通过油性鱼类、肉类和乳制品等食物。多溴二苯醚暴露和身体负担对人类健康的潜在影响是生殖毒性、神经毒性、免疫效应和致癌性。包含所有潜在来源、途径和受体的风险评估可表示为概念暴露模型(CEM)。这项研究的假设是：1.粉尘和空气中的多溴二苯醚浓度可以根据房间或车辆内的内容物(例如电脑/地毯的数量/年龄)来预测；2.包括饮食、室内环境和行为在内的CEMS可用于预测多溴二苯醚的身体负荷；3.室内暴露于多溴二苯醚是总暴露的重要因素；(对于传统的持久性有机污染物饮食是主要来源)；4.多溴二苯醚在血液和母乳等隔间的分布由其物理化学性质决定。该方案将进一步了解多溴二苯醚的降解和代谢，以及环境和人体样本中多溴二苯醚的相关来源。在研究过程中，将开发数学模型来预测在各种情况下未来的暴露。最终的研究成果将是基于证据的暴露管理战略和风险评估。两年以上未搬家或未转业的同居夫妻将被录用。使用这样的夫妇将允许对共享的饮食和室内环境进行采样和分析，并识别因玩电脑游戏或工作暴露等行为而产生的差异。身体负担将通过血液样本进行评估。将对饮食、室内空气和粉尘样本进行评估，并将使用全面的问卷和调查来创建CEM。粉尘和空气中的多溴二苯醚浓度将通过对房间或车辆内容物的全面调查来预测。大约一半的培训和所有实地工作将设在纽卡斯尔大学的健康与社会研究所。伯明翰大学环境健康和风险管理部将提供室内空气环境监测和采样方面的培训，以及阻燃剂研究方面的专业知识。中央科学实验室的食品科学小组将提供饮食研究和暴露评估方法以及分析化学技术方面的技术培训。这些研究中心都走在各自领域的前沿，它们的合作是因为需要对持久性有机污染物的调查和建模采取综合办法。通过这一能力建设计划，学生将在多学科研究和合作方面获得宝贵的经验，同时开创一种新的BFR暴露特征的方法。与全国持久性有机污染物网络的联系为传播成果和进一步研究机会提供了肥沃的土壤。

Legislation requiring flame retardants to be added to soft furniture and electronic items since the 1970s has saved many lives. Brominated Flame Retardants (BFRs) including Poly Brominated Diphenyl Ethers (PBDEs) are now ubiquitous in the environment and bio-accumulate. The Stockholm Convention (2004) requires signatories to reduce or eliminate releases of unintentionally and intentionally produced Persistent Organic Pollutants (POPs) to protect human health and the environment. Emerging POPs such as PBDEs may soon be included in the 'dirty dozen'. Little is known about the magnitude and exposure pathways of PBDEs. They are released during manufacture, recycling and incineration processes, can leach from treated materials into the atmosphere and can be absorbed by dermal contact. The human body burden of PBDE has doubled every five years for the past 30 years. PBDEs are lipophilic, accumulating in human fatty tissue. Transfer from mother to child occurs during breast feeding. Young children spending time on carpets and exhibiting frequent hand to mouth behaviour are known to have increased body burden. Another route of exposure to POPs is via food such as oily fish, meat and dairy. The potential human health effects of PBDE exposure and body burden are reproductive toxicity, neurotoxicity, immune effects and carcinogenicity. A risk assessment incorporating all potential sources, pathways and receptors can be expressed as a Conceptual Exposure Model (CEM). The hypotheses of this research are: 1. PBDE concentrations in dust and air can be predicted from room or vehicle contents (e.g. number/age of computers/carpeting); 2. CEMs including diet, indoor environments and behaviours can be used to predict body burdens of PBDE; 3. Indoor exposures to PBDE are an important contributor to overall exposure; (for legacy POPs diet is the major source); 4. The distribution of PBDEs between compartments such as blood and breast milk is determined by their physico-chemical properties. The programme will further the understanding of degradation and metabolism of PBDEs and correlate sources of PBDE in environmental and human samples. During the research process mathematical models will be developed to predict future exposures under a variety of scenarios. The final research outcomes will be evidence based exposure management strategies and risk assessments. Co-habiting couples who have not moved house or changed employment for at least 2 years will be recruited. Using such couples will allow sampling and analysis of shared diet and indoor environments and identification of differences resulting from behaviours such as computer gaming or work exposures. Body burden will be assessed from blood samples. Diet, indoor air and dust samples will be assessed and comprehensive questionnaires and surveys will be used to create the CEMs. PBDE concentrations in dust and air will be predicted using comprehensive surveys of room or vehicle contents. Approximately half the training and all fieldwork will be based Newcastle University's Institute of Health and Society. Birmingham University's Division of Environmental Health and Risk Management will provide training in monitoring and sampling of indoor air environments as well as expertise in flame retardants research. The Food Science Group at Central Science Laboratory will provide technical training in diet studies and exposure assessment methodology as well as analytical chemistry techniques. The collaboration of these research centres, each at the forefront of their field, is driven by the need for an holistic approach to POPs investigation and modelling. Through this capacity building programme the student will gain valuable experience in multidisciplinary research and collaboration whilst pioneering a new approach to BFR exposure characterisation. The association with the NERC POPs Network provides fertile ground for dissemination of results and further research opportunities.