The brown light reflection in the anterior chamber of the eye lens is thought to be a “mercury lensitis” caused by mercury deposition, which can persist after the symptoms of poisoning disappear or after removal from mercury exposure, and is another marker of mercury absorption. What are the tests for mercury poisoning? 1. Urine mercury reflects to some extent the amount of mercury absorption in the body, but often has no parallel relationship with the clinical symptoms and severity of mercury poisoning. Urine mercury test is a urine ion test. The increase of urine mercury reflects the increase of mercury absorption in human body, which is of auxiliary significance for the diagnosis of mercury poisoning, especially acute mercury poisoning. 2.Blood mercury measurement reflects the absorption of mercury in the body to a certain extent, but it often has no parallel relationship with the clinical symptoms and severity of mercury poisoning. Mercury is a silvery-white liquid metal, which evaporates at room temperature. Mercury is one of the heavy metals commonly used in battery and mining industries. Mercury and its compounds can enter the human body through different routes such as respiratory, skin or digestive tract. The toxicity of mercury is cumulative and takes a long time to manifest itself. Urine mercury and blood urine measurements reflect to some extent the amount of mercury absorbed in the body, but often have no parallel relationship with the clinical symptoms and severity of mercury poisoning. The normal value of urine mercury varies from region to region, and the normal upper limit of urine mercury in China generally does not exceed 0.25 μmol/L (0.05 mg/L) by dithizone thermal nitration method or 0.1 μmol/L (0.02 mg/L) by atomic energy absorption method. The normal upper limit of blood mercury is 1.5μmol/L (0.03mg/dl). 3, EEG There may be changes in EEG wave amplitude and rhythmic electrical activity, slowed peripheral nerve conduction velocity, increased blood a2 globulin and reduced glutathione, as well as decreased blood lysosomal enzymes, erythrocyte cholinesterase and serum sulfhydryl groups. EEG is a graph obtained by amplifying and recording the spontaneous biopotential of the brain from the scalp through an instrument. 4.X-ray chest film can be seen in both lungs with widespread irregular shadows, more or less fused into points, lamellar shadows, or hairy glass-like interstitial changes.