Introduction Paddy fields in Mae Sot, Tak province of Thailand are polluted with cadmium (Cd) over safe level. Farmers exposed Cd from contaminated rice consumption and the high prevalence of kidney dysfunction was shown in the exposed population. Bone fracture is another Cd related pathology which shown in elderly with high exposure level. The identification of high risk individuals will be advantageous to provide suitable health promotion and to prevent severe pathology.This study was done to compare bone fracture risk between glomerular dysfunction, proximal tubular dysfunction and Calcium (Ca) handling abnormality.

Methods Serum osteocalcin and cross-linked N-telopeptide of type I collagen to detect bone metabolism abnormalities, whereas glomerular filtration rate, serum cystatin C, urinary β2-microglobulin (β₂-MG) and fractional excretion of calcium (FECa) were used to indicate renal dysfunction. Urinary Cd was used as exposure marker.

Results We found that high FECa was related to high bone fracture risk in both genders. Proximal tubular dysfunction and glomerular dysfunction did not relate to bone fracture risk.

Conclusion Abnormal Cd handling was a key risk factor for bone fracture in Cd exposed people. Men was at risk of bone fracture risk as similar as women. FECa was a specific indicator of Ca wasting and its determination cost was cheaper compare to β₂-MG and serum cystatin C. We recommended to use FECa to monitor abnormal Ca metabolism and individual who showed high FECa should have a special health promotion to reduce bone fracture risk. Reduced renal toxicant exposure, and Ca supplementation were suggested as a health promotion for this Cd exposed farmer.