Table 8. Maximal acceptable level and negligible level recommended by different institutions.

Institutions	Maximum risk level	Ignore the level of risk	Remarks
USEPA	1 × 10−4	–	Radiation
ICRP	5 × 10−5	–	Radiation
Royal Association of England	1 × 10−6	1 × 10−7	–
Holland Environmental Protection Agency	1 × 10−6	1 × 10−8	Chemical contaminants
Swedish Environmental Protection Agency	1 × 10−6	–	Chemical contaminants