<prompt> Mees line on nail is diagnostic of -Lead poisoningArsenic poisoningWhite phosphorus poisoningMercury poisoning  <response>: Ans. is b i.e., Arsenic poisoning Chronic arsenic poisoningo First stage of gastrointestinal nutritional disturbance:Gradual emaciation is earliest signAnorexia, nausea, vomiting, diarrhoea abdominal crampso Second catarrhal stageFeatures of common cold, bronchial catarrhal, coughing hoarsenesso Third stage of skin rashSkin irritation, vesicular eruption resembling nettle rashPatchy brown raindrop type pigmentationHyperkeratosis of palms solesFalling of hair brittleness of nailWhite transverse band or Meefs line on nailo Fourth stage of nervous disturbanceSensory motor neuropathy causing tingling, numbness paresisEncephalopathyo Bone marrow suppression, anemia, weight loss, hepatomegaly, cirrhosis, nephritis, thrombocytopenia, leukemia, skin, lung, liver, bladder kidney cancer and exfoliative dermatitis diabetes. 