Amato-Lourenço Luís Fernando, Dantas Katia Cristina, Júnior Gabriel Ribeiro, Paes Vitor Ribeiro, Ando Rômulo Augusto, de Oliveira Freitas Raul, da Costa Ohanna Maria Menezes M, Rabelo Renata S, Soares Bispo Kelly Cristina, Carvalho-Oliveira Regiani, Mauad Thais
Institute of Biology, Freie Universität Berlin, Berlin, Germany.
Department of Pathology, Sao Paulo Medical School, University of São Paulo, São Paulo, Brazil.
JAMA Netw Open. 2024 Sep 3;7(9):e2440018. doi: 10.1001/jamanetworkopen.2024.40018.
Microplastic (MP) pollution is an emerging environmental and health concern. While MPs have been detected in various human tissues, their presence in the human brain has not been documented, raising important questions about potential neurotoxic effects and the mechanisms by which MPs might reach brain tissues.
To determine the presence of MPs in the human olfactory bulb and to analyze their characteristics such as size, morphology, color, and polymeric composition.
DESIGN, SETTING, AND PARTICIPANTS: This case series study used a cross-sectional design involving the analysis of olfactory bulb tissues obtained from deceased individuals during routine coroner autopsies. The sampling procedures were conducted at São Paulo City Death Verification Service, with laboratory analysis carried out at the Brazilian Synchrotron Light Laboratory (LNLS). Participants included 15 adult individuals who had been residents of São Paulo for more than 5 years and underwent coroner autopsies. Exclusion criteria included previous neurosurgical interventions. Data analysis was performed in April 2024.
The primary exposure assessed was the presence of MPs in the olfactory bulb, analyzed through direct tissue examination and digested tissue filtration followed by micro-Fourier transform infrared spectroscopy.
The main outcomes were the identification and characterization of MPs within the olfactory bulb, including their size, morphology, color, and polymeric composition.
The median age of the 15 deceased individuals was 69.5 years, ranging from 33 to 100 years, with 12 males and 3 females. MPs were detected in the olfactory bulbs of 8 out of 15 individuals. A total of 16 synthetic polymer particles and fibers were identified, with 75% being particles and 25% being fibers. The most common polymer detected was polypropylene (43.8%). Sizes of MPs ranged from 5.5 μm to 26.4 μm for particles, and the mean fiber length was 21.4 μm. Polymeric materials were absent in procedural blank and negative control filters, indicating minimal contamination risk.
This case series provides evidence of MPs found in the human olfactory bulb, suggesting a potential pathway for the translocation of MPs to the brain. The findings underscore the need for further research on the health implications of MP exposure, particularly concerning neurotoxicity and the potential for MPs to bypass the blood-brain barrier.
微塑料（MP）污染是一个新出现的环境和健康问题。虽然已在人体各种组织中检测到微塑料，但尚未有其存在于人类大脑中的记录，这引发了关于潜在神经毒性作用以及微塑料可能进入脑组织的机制的重要问题。
确定人类嗅球中微塑料的存在情况，并分析其大小、形态、颜色和聚合物组成等特征。
设计、地点和参与者：本病例系列研究采用横断面设计，涉及对在验尸官常规尸检期间从死者身上获取的嗅球组织进行分析。采样程序在圣保罗市死亡核查服务处进行，实验室分析在巴西同步加速器光实验室（LNLS）开展。参与者包括15名成年个体，他们是圣保罗居民且居住超过5年，均接受了验尸官尸检。排除标准包括既往有神经外科手术史。数据分析于2024年4月进行。
评估的主要暴露因素是嗅球中微塑料的存在情况，通过直接组织检查和消化组织过滤，随后进行微傅里叶变换红外光谱分析。
主要结局是嗅球内微塑料的识别和特征描述，包括其大小、形态、颜色和聚合物组成。
15名死者的年龄中位数为69.5岁，年龄范围为33至100岁，其中男性12名，女性3名。15名个体中有8名在嗅球中检测到微塑料。共识别出16个合成聚合物颗粒和纤维，其中75%为颗粒，25%为纤维。检测到的最常见聚合物是聚丙烯（43.8%）。颗粒状微塑料的大小范围为5.5μm至26.4μm，纤维的平均长度为21.4μm。程序空白和阴性对照滤膜中未发现聚合物材料，表明污染风险极小。
本病例系列提供了人类嗅球中存在微塑料的证据，提示微塑料向大脑转移的潜在途径。这些发现强调了有必要进一步研究微塑料暴露对健康的影响，特别是关于神经毒性以及微塑料绕过血脑屏障的可能性。
