Department of Physiological Sciences, Federal University of São Carlos, Rod Washington Luis km 235, 13565-905 São Carlos, SP, Brazil.
Department of Physiological Sciences, Federal University of São Carlos, Rod Washington Luis km 235, 13565-905 São Carlos, SP, Brazil.
Comp Biochem Physiol C Toxicol Pharmacol. 2022 Jul;257:109330. doi: 10.1016/j.cbpc.2022.109330. Epub 2022 Mar 21.
Steel industry emissions of atmospheric particulate matter are responsible for air to water cross-contamination, which deposits metal/metalloid contaminants in aquatic ecosystems. This source of contamination has not been considered in most of the environmental monitoring protocols. Settleable atmospheric particulate matter (SePM) collected in an area of steel industry influence was used to analyze the sublethal effects on the hematological and innate immunological variables in Nile tilapia (Oreochromis niloticus) after short-term exposure (96 h). Blood samples were analyzed to evaluate the oxygen-carrying transport capacity, innate immune activity and stress biomarkers after exposure to ecologically relevant concentration of SePM. The exposure reduced blood oxygen-carrying capacity by lessening hematocrit, hemoglobin, erythrocyte, and mean corpuscular hemoglobin concentration. Compensatory increments in mean corpuscular volume and mean corpuscular hemoglobin have also been observed. The contaminant impacted the immune system by reducing the number of leukocytes, thrombocytes, and monocytes, total plasma protein, leukocyte respiratory activity, and by increasing lysozyme concentration. Furthermore, the contaminant caused endocrine stress response, raising plasma cortisol and glucose. Therefore, the alterations caused by SePM threatened the capacity of sustaining aerobic metabolism, impaired the immune system, and changed the energy allocation due to both stress response and immune effect. This may have important implications for the impact of SePM on aquatic ecosystems. Future investigations should assess SePM impact on general physiology and aerobic performance, especially to face common ecological challenges such as hypoxia and sustained swimming. These results point out the need to develop proper protocols to address the air-to-water cross-contamination risks by iron ore processing industries.
钢铁行业排放的大气颗粒物是造成空气与水交叉污染的原因，这些污染物会将金属/类金属污染物沉积在水生生态系统中。这一污染源在大多数环境监测方案中都没有被考虑到。本研究采用沉降大气颗粒物（SePM）来分析短期暴露（96 小时）对尼罗罗非鱼（Oreochromis niloticus）血液学和先天免疫变量的亚致死效应。采集暴露于生态相关浓度 SePM 的血液样本，分析血液中氧载体的运输能力、先天免疫活性和应激生物标志物。暴露会降低血液中氧载体的运输能力，减少红细胞比容、血红蛋白、红细胞和平均红细胞血红蛋白浓度。还观察到平均红细胞体积和平均红细胞血红蛋白的代偿性增加。该污染物通过减少白细胞、血小板和单核细胞数量、总血浆蛋白、白细胞呼吸活性和增加溶菌酶浓度来影响免疫系统。此外，污染物还会引起内分泌应激反应，增加血浆皮质醇和葡萄糖水平。因此，沉降颗粒物引起的变化威胁到维持需氧代谢的能力，损害免疫系统，并由于应激反应和免疫效应改变能量分配。这可能对沉降颗粒物对水生生态系统的影响具有重要意义。未来的研究应评估沉降颗粒物对一般生理和需氧性能的影响，特别是要应对缺氧和持续游泳等常见生态挑战。这些结果表明，需要制定适当的方案来解决铁矿加工行业空气与水交叉污染的风险。
