Table 13 Selected neoplastic and non-neoplastic lung effects in 2 year inhalation studies of male and female F344/N rats and B6C3F₁ mice exposed to nickel subsulphide, nickel oxide and nickel sulphate hexahydrate [30–32]; and Wistar rats exposed to nickel metal powder [35]

Ni species, dose and lung effects

Male

Female

Male

Female

Nickel subsulphide:

   Dose in % of MTD^{a, b}

(0, 15, 100)

(0, 15, 100)

(0, 50, 100)

(0, 50, 100)

   Chronic active inflammation rate

(9/53, 53/53, 51/53)

(7/53, 51/53, 51/53)

(1/61, 52/59, 53/58)

(1/58, 46/59, 58/60)

   Macrophage hyperplasia rate

(9/53, 48/53, 52/53)

(8/53, 51/53, 52/53)

(6/61, 57/59, 58/58)

(5/58, 57/59, 60/60)

   Alveolar/bronchiolar adenoma or carcinoma rate

(0/53, 6/53, 11/53)

(2/53, 6/53, 9/53)^f

None

None

Nickel oxide:

   Dose in % of MTD^c

(0, 25, 50, 100)

(0, 25, 50, 100)

(0, 25, 50, 100)

(0, 25, 50, 100)

   Chronic inflammation rate

(28/54, 53/53, 53/53, 52/52)

(18/53, 52/53, 53/53, 54/54)

(0/57, 21/67, 34/66, 55/69)

(7/64, 43/66, 53/63, 52/64)

   Alveolar/bronchiolar adenoma or carcinoma rate

(1/54, 1/53, 6/53, 4/52)^f

(1/53, 0/53, 6/53, 5/54)

None

(6/64, 15/66, 12/63, 8/64)

Nickel sulphate hexahydrate:

   Dose in % of MTD^d

(0, 25, 50, 100)

(0, 25, 50, 100)

(0, 25, 50, 100)

(0, 25, 50, 100)

   Chronic active inflammation rate

(14/54, 11/53, 42/53, 46/53)

(14/52, 13/53, 49/53, 52/54)

(1/61, 2/61, 8/62, 29/61)

(1/61, 7/60, 14/60, 40/60)

   Macrophage hyperplasia rate

(7/54, 9/53, 35/53, 48/53)

(9/52, 10/53, 32/53, 45/54)

(6/61, 9/61, 35/62, 59/61)

(7/61, 24/60, 53/60, 59/60)

   Neoplastic effects

None

None

None

None

Nickel metal:

   Dose in % of MTD^e

(0, 25, 100)

(0, 25, 100)

   Chronic inflammation rate

(14/50, 44/50, 41/50)

(16/50, 45/50, 45/54)

   Neoplastic effects

None^g

None^g