Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

Key value for chemical safety assessment

Additional information

Oral exposure

In an investigation to provide preliminary information about the absorption, distribution and excretion of the substance after single oral exposure, ZPS was labelled with 65Zn (The Procter & Gamble Company, 1979). When the substance was dosed orally to rats at a dose level of 10.8 mg/kg bw most (91.4%) of the recovered 65Zn was recovered in the faeces. The 0-24 hour faecal collection had 90.4% of this total. Less than 0.5% of the 65Zn was found in the tissues collected at necropsy, although the bone concentration at 0.388 µg/g and the bone marrow concentration at 0.255 µg/g was around ten times higher than the blood concentration. The concentration of radioactivity in the blood (0.039 µg/g) was higher than that in the plasma (0.012 µg/g) at necropsy, indicating that the removal of radioactivity from the blood cells was not as rapid as from the plasma. The carcass contained 1.12% of the 65Zn after the tissue removal. The total Zn recovery was 96.1%.

 

In another investigation to provide preliminary information about the absorption, distribution and excretion of the substance after single oral exposure, ZPS was labelled with 14C (The Procter & Gamble Company, 1978). When the substance was dosed orally to rats at a dose level of 6.71 mg/kg bw there was very little absorption of the compound. Most of the recovered 14C was in the faeces (98.3%). The 0-24 hour faecal collection interval contained 92.1% of this total. The residue in the tissues and carcass was very low (~0.18%), with 0.06% of this total in the liver at the 72 hour necropsy. The CO2 did not contain any of the recovered 14C. The recovery was excellent with 99.7% of the dosed 14C accounted for. The amount of radioactivity found in the tissues was so low that it could be accounted for by absorption of radiochemical impurities in the dosing preparation. The possibility that the test material might be absorbed and then be excreted in the bile cannot be excluded, but it appears unlikely.

Oral absorption is assumed to be 2%.

Dermal exposure

In an investigation to provide preliminary information about the absorption, distribution and excretion of the substance after single dermal exposure, ZPS was labelled with 14C (The Procter & Gamble Company, 1978). When the substance was dosed cutaneously at a dose level of 6.68 mg/kg bw, most of the 14C was recovered at the test site. 94.6% of the 96.8% 14C recovered was on the skin, indicating very little absorption of the compound. Less than 0.1% of the dosed radioactivity was found in the tissues, carcass, urine and faeces. This percentage is so small that it may represent either the test compound or radiochemical impurities present in the dosing preparation. The recovery was excellent with 96.8% of the dosed 14C accounted for.

In another investigation to provide preliminary information about the absorption, distribution and excretion of the substance after single dermal exposure, ZPS was labelled with 65Zn (The Procter & Gamble Company, 1979). When the substance was dosed cutaneously to the rat at a dose level of 9.2 mg/kg bw, all of the 65Zn was recovered at the test site. The concentration of radioactivity in the tissue and carcass samples was below the detection limit for nearly every sample. The overall recovery was 103±1%. No detectable absorption of the test compound occurred under the conditions of this test.

 

Dermal absorption is assumed to be 0.1%

Intratracheal exposure

In an investigation to provide preliminary information about the absorption, distribution and excretion of the substance after single intratracheal exposure, ZPS was labelled with 65Zn (The Procter & Gamble Company, 1977). When the substance was dosed to rats intratracheally at dose levels of 5, 50 and 500 µg, the recovery in the urine averaged approximately 1% for the high dose level. ZPS was not detected for the two lower dose levels.