Land exploitation that follows deforestation and mining can result in soil erosion and the release of mercury to the waters of rivers in the Amazon Basin. Inorganic mercury is methylated by bacteria that are present in the environment and it serves as a source of human contamination through fish consumption in the form of methylmercury. Long-term exposure to low-level methylmercury in the riverside populations can lead to nervous system alterations, some of which are visual impairments such as loss of luminance contrast sensitivity, restricted visual fields and color vision defects. The present study sought to examine color vision in a group of adults living in the central Brazilian Amazon who were exposed to low-levels of methylmercury. Total Hg concentrations were measured from hair collected at the time of the testing. The D15d and FM100 color vision arrangement tests were applied in a population of 36 (22 males) and 42 (25 males), respectively. Controls were healthy volunteers from the cities of São Paulo for the D15d and Belém for the FM100. There was a statistically significant difference in performance between those who were exposed and controls for both tests (p < 0.01 and p < 0.0001, respectively, Mann-Whitney U test), meaning that adults living in this region of the Amazon made more mistakes on both tests when compared to controls. A linear regression was performed using Hg concentrations and test scores. Hg concentrations accounted for 7% and 2% of color D15d and FM100 arrangement test errors, respectively. Although other studies have previously found color vision impairment in the Amazon, they tested inhabitants on the east side of the Amazon, while this study was conducted in the central Amazon region and it is the first study in a population with no direct contact with the Hg source of contamination. These results suggest that long-term exposure to low-level methylmercury in riverside populations is more widely spread in the Amazon Basin than previously reported. This information is needed to implement public health policies that will ensure a safer environment for the Amazonian population.

毁林和采矿之后的土地开发会导致水土流失和汞向亚马逊河流域河流水域的释放。无机汞被环境中存在的细菌甲基化，并通过食用甲基汞形式的鱼类而成为人类污染的来源。沿河地区人口长期接触低水平甲基汞会导致神经系统改变，其中一些是视觉障碍，例如亮度对比敏感度降低，视野受限和色觉缺陷。本研究试图检查居住在巴西中部亚马逊河谷的一群成年人的色觉，这些成年人暴露于低水平的甲基汞。从测试时收集的头发中测量总Hg浓度。D15d和FM100彩色视觉布置测试分别应用于36位（22位男性）和42位（25位男性）的人群。对照组是圣保罗市的D15d健康志愿者和贝伦市的FM100健康志愿者。两种测试的暴露者和对照组之间的表现在统计学上都有显着差异（分别为p <0.01和p <0.0001，Mann-Whitneyü测试），这意味着与对照组相比，居住在亚马逊地区的成年人在两种测试中都犯了更多的错误。使用汞浓度和测试分数进行线性回归。汞浓度分别占颜色D15d和FM100布置测试误差的7％和2％。尽管之前有其他研究在亚马逊河发现色觉受损，但他们在亚马逊河东侧对居民进行了测试，而这项研究是在亚马逊河中部地区进行的，这是首次与汞没有直接接触的人群的研究。污染源。这些结果表明，与之前报道的情况相比，亚马逊河沿岸地区长期接触低水平甲基汞的人群分布更广。