Medical and non-medical correlates of carpal tunnel syndrome in a Taiwan cohort of one million.

BACKGROUND: Carpal tunnel syndrome (CTS), with unclear etiology, is the most common entrapment neuropathy. Its occurrence is related to lots of medical and non-medical conditions with uncertain causality. With a large population, we characterized selected demographical and clinical factors to add more information on CTS-correlated factors and new insight into future CTS prevention. METHODS: A national insurance claim dataset of one million enrollees in Taiwan was used to identify 15 802 patients with CTS and 31 604 randomly selected controls, during a period of 7 years starting 1 January 2000. Statistical association with CTS was determined for five sociodemographic and nine medical factors. RESULTS: Patients were predominantly women (65.6% vs. 47.7% in the control group) and older (40 and above, 62.6% vs. 36.2%). Rheumatoid arthritis was found to be the most significant comorbidity associated with CTS, followed by gout, hypertension, diabetes, obesity, uremia, and acromegaly. For younger group age ≤39, the association of these comorbidities was stronger, and hypothyroidism and vitamin B(6) deficiency were additional comorbidities. Aging appears to reduce the relative impact of the diseases commonly associated with CTS as the possible risk factors. CONCLUSIONS: Identification of the CTS correlates in younger group would be of greater value in timely detection and treatment for these diseases. Correcting these disorders may aid in removing possible causes of CTS. This is the first report on the effect of aging on probable CTS risk factors. How factors associated with aging contribute to the development of CTS remains to be determined.

Toxicological analysis points to a lower tolerable daily intake of melamine in food.

Intensified food safety concern over melamine has prompted national authorities to assess its tolerable daily intake (TDI) for protection of general population including young children. TDI is calculated by dividing a no-observed-adverse-effect level (NOAEL) by a safety factor (SF). Based on appropriate choices of values, the US Food and Drug Administration determined two TDI values in the unit of mg per kg body weight per day as first 0.63 and then 0.063, while the World Health Organization, 0.5 and then 0.2, as a result of increasing the SF values in calculation. We used a similar procedure, with judicious selection of pertinent values, to obtain a TDI of 0.0081. Arguments in support of this lower TDI value were provided to alert the international community.

Toxicity identification evaluation (TIE) of pore water of contaminated marine sediments collected from Hong Kong waters.

Marine sediment can function both as a source and as a sink of marine chemical contaminants. The toxicity of contaminated marine sediment can be assessed by toxic evaluation of its pore water, the inter-particle water of sediment, because toxicants in the pore water may be bioavailable to marine organisms. In this study, the toxicity identification evaluation (TIE) was performed to identify the major toxicants in the pore water of marine sediment collected in Hong Kong waters. In Phase 1 TIE, the suspected toxicants were characterized as anions or organic compounds that are either oxidizable or filterable in alkaline medium. In Phase 2 TIE, the suspected toxicants were identified as sulfide (S(2-)) based on the reduction of toxicity due to lowering of sulfide concentrations by experimental manipulations. The mass balance and spiking analyses in Phase 3 confirmed that S(2-) was one of the major toxicants and that some non-toxic unknown compounds measured by LC-MS, which was removed by C18 solid phase extraction, enhanced the toxicity of S(2-) in the pore water samples.

Application of a toxicity identification evaluation for a sample of effluent discharged from a dyeing factory in Hong Kong.

A first toxicity identification evaluation (TIE) was conducted in three phases using the Microtox test to identify the major toxicant(s) in effluent discharged from a dyeing plant in Hong Kong. In Phase I toxicity characterization indicated that anions were likely to be the major toxicants for the entire effluent. In Phase II concentrations of sulfite and other anions in the original and the anion exchange resin-treated effluent samples were determined by ion chromatography. Anions, which were found in the effluent at comparatively high concentrations and were suspected of being responsible for the toxicity to luminescent bacteria, were selected for further study in Phase III. Investigation in Phase III using the spiking and mass balance approaches confirmed that the sulfite ion was the major toxicant in the effluent.