四间公社位于黑山县城东。水质含氟量平均3毫克/升,水质硬度18.2～29.0度。本次调查7岁以上居民359人,其中斑釉齿334人,患病率为93％;氟中毒患者159人,患病率为44.3％。斑釉病Ⅲ°居多,氟中毒以轻度居多,临床症状以腰背痛及下肢痛为多(96人),头痛者亦不少见(42人)。从体征表现看,以肢体变形(尤以上肢时关节屈 The four communes are located in the east of Heishan County. Average water quality fluorine 3 mg / l, water hardness 18.2 ~ 29.0 degrees. The survey of residents over the age of 7 359 people, of which spot glazed tooth 334 people, the prevalence was 93%; 159 patients with fluorosis, the prevalence was 44.3%. Spot glaze disease Ⅲ ° mostly fluorosis mostly mild clinical symptoms of low back pain and lower limb pain (96), headache are not uncommon (42). From the signs of performance to limb deformity (especially when the upper limb flexor