PELMEAR PL, ROOS J, LEONG D, WONG L. Cold provocation test results from a 1985 survey of hard-rock miners in Ontario. Scand J Work Environ Health 13 (1987) 343-347. A total of 143 miners, 6 ex-miners, and 42 referents from five mines in northern Ontario were examined with a cold provocation test. The skin temperatures , measured by thermocouples at the tips of the fingers and thumbs were recorded at 5-s inter vals throughout the immersion in cold water (IO°C) for 10 min and durin g the recovery

more »

... period . The finger skin temperature was followed until 99 070 recovery had occurred as compared to the starting temperature. For the referents and the vibration-exposed subjects, the results by separate stage of the Taylor-Pelmear scale for hand-arm vibration syndrome were compared . There were statistically significant differenc es in the mean finger temperature at the 50, 75, 90, and 95 0J0 recovery times between stages 0, 0T/O N , and stages I through 3 comb ined, as well as significant differences between stages I, 2, and 3. The mean temperature at 10 min and the mean hyperemia temperature for eight fingers combined were compared between the miner s and referents. There were significant differences in the mean temperature at 10 min and in the hyperemi a temperature between the referents and miners in stage~/ON' as well as between the referents and the miners in stages I through 3 combined. For the worst finger (defined as that with the lowest temperature at 10 min) there was an increasing trend towards a lower hyperemia tempera ture and delay in recovery time from stage 0 to stages 2 and 3 combined. Comparison of the positive predictive values of the cold provocation test results for the worst finger supports the use of a staging of blanched fingers based on social and work interference as the grade of severity, rather than the use of a blanching index rating . Key terms: finger skin temp erature, Raynaud 's phenomenon. Objective te sts to confirm the presence of Raynaud's phenomenon and grade its severity are sorely needed by clinicians, particularly in field st ud ies. The cold provo cation te st has been frequently used for such purposes, and the present investigation was ca rr ied out to evaluate this use . Subjects A total of 227 miner s or ex-miners and 60 referents were examined from five mines in northern Ont ario. Ninety-six subjects were rejected from the analysis because of a history of trauma, an abnormal medical history, or an unsatisfactory clinical state . A tot al of 143 miners , 6 ex-miners, and 42 referent s remained (table I) . The mean age of the referent s was 34.8 years, and that of the miner s 35 years. The daily exposure to vibratory tool s averaged 2.1 h. Th e prevalence of finger blanching by Taylor-Pelme ar stages I , 2, and 3 of the hand -arm vibration syndrome (2) was 43 % amon g the miner s, and the mean latency interval was 10.4 years. Methods As previously described (I), each subject was examined lying down with his body and legs completely wrapped in an elec-I Health and Safet y Support Services Branch, Ontario Ministry of Labour, Toronto, Canada.