Table 2.

General characteristics of the study population in the Three Gorges Reservoir Region.^a

Parameter	Unexposed children	Low-exposed children	High-exposed children	p-Value
No. (%)		145 (11)		183 (14)		994 (75)		–
Male:female (%)		52:48		54:46		51:49		0.75b
Age (years)		11.2 ± 1.8		10.3 ± 0.7		11.6 ± 2.5		0.03c
HBV infection (n)		3		4		37		0.39b
Hepatotoxic medicines used (n)		7		9		65		0.55b
Consumption of water per child per day (L)		1.1 ± 0.5		1.2 ± 0.6		1.1 ± 0.4		0.09c
Strenuous exercise [yes:no (n)]		18:127		28:155		162:832		0.48b
BMI (n)								0.23b
< 16		39		49		288
16–18		51		62		391
> 19		55		72		315
Frequency of aquatic food consumption (n)								0.39b
< 1 time/weekd		12		11		81
1–2 times/week		73		89		487
3–6 times/week		47		65		367
> 6 times/week		13		18		59
Smoking status (n)								0.001b
Nonpassive smoker		102		116		878
Passive smoker		42		67		110
Smoker		1		0		8
aValues are mean ± SD except where noted. bFrom chi-square test. cFrom Kruskal–Wallis test. dIntake of child = 25 g aquatic food each time.