SUMMARY OF HAIR MERCURY ANALYSIS

Hair sample was collected from delegates of the Conference at the NIMD booth in the Conference site during 28th to 31th June 2013. Total mercury concentration was determined, as a methylmercury exposure marker, with a mercury analyzer MA-300 (Nippon Instruments, Co., Ltd., Tokyo). Analytical result was given to each participant by hand or mail.

The total number of participants tested was 240, consisting of 114 females and 126 males, from 43 countries. Participants included 103 delegates from Europe, 75 from North America and 39 from Asia (Table 1). The largest age group was 30 to 39 years of age, and 88.2% were between 20 and 59 years of age (Table 2).

The mercury concentration was widely distributed, ranging from 0.01 to 12.74 ppm, as shown in Fig. 1. The mean concentration (geometric mean) was 0.49 ppm, with 0.41 ppm in females and 0.57 ppm in males (Table 3).

Regional differences in the geometric mean (GM) were shown in Fig. 2. The highest mean was observed in participants from Japan, and relatively high GMs were found in East/South East Asia (excluding Japan) and Central/South America.

Hair mercury concentration was significantly correlated with frequency of fish consumption. The mean concentration (GM) in participants who eat fish every day was twenty-fold or higher than in participants who never eat. The fish consumption dependent difference was more significant in males (by a factor of 26.9) than in females (by a factor of 14.6).

Table 1． Number of participants of hair mercury analysis

Area	Female	Male	Total
Europe	60	43	103
North America	34	41	75
South America	7	11	18
Africa	1	3	4
Oceania	0	1	1
West and South Asia	3	3	6
East and South East Asia (Japan)	9 (5)	24 (8)	33 (13)
Total	114	126	240

Table 2. Number of participants by age class

Gender	Age class
	0-	10-	20-	30-	40-	50-	60-	70-	Not specified	Total
Female	3	3	24	44	21	15	3	0	1	114
Male	2	0	18	33	30	25	15	2	1	126
Total	5	3	42	77	51	40	18	2	2	240

Table 3．Range and geometric mean of hair mercury concentration (ppm)

Gender	Min	Max	Geometric mean
Female	0.01	6.17	0.41
Male	0.01	12.74	0.57
Total	0.01	12.74	0.49