Calcium sulphidoacetate

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 110 (Particle Size Distribution / Fibre Length and Diameter Distributions)

GLP compliance:

yes (incl. QA statement)

Type of method:

sedimentation (gravitational settling)

Type of particle tested:

primary particle

Type of distribution:

mass based distribution

Percentile:

other: D83

Mean:

<= 105.2 µm

Remarks on result:

other: appr. 17% of the particles have a diameter >105.2 µm

Percentile:

D10

Mean:

>= 1 - < 7 µm

Remarks on result:

other: SD not reported

Percentile:

D50

Mean:

>= 1 - <= 20.4 µm

Remarks on result:

other: SD not reported

Percentile:

D90

Mean:

>= 1 - <= 61.9 µm

Remarks on result:

other: SD not reported

   Comparison Three Experiments (measurable part)

Stokes-diameter in µm	Mass under particle size Exp. 1	Mass under particle size Exp. 2	Mass under particle size Exp. 3	Mass under particle size Mean	Difference
	meas. part	meas. part	meas. part	meas. part
105.16	98.84%	97.65%	99.42%	98.63%	1.77%
61.92	94.77%	94.71%	97.66%	95.71%	2.95%
43.04	87.21%	91.18%	93.57%	90.65%	6.36%
34.53	79.65%	82.94%	85.38%	82.66%	5.73%
26.26	65.12%	67.06%	67.84%	66.67%	2.72%
20.37	50.00%	50.00%	51.46%	50.49%	1.46%
14.12	29.07%	28.24%	28.65%	28.65%	0.83%
9.78	16.28%	14.71%	16.37%	15.79%	1.67%
6.77	7.56%	6.47%	9.94%	7.99%	3.47%
4.68	5.81%	5.29%	7.60%	6.24%	2.31%

meas. part = measurable part = 109.4 – 110.7% of total test item

Executive summary:

All measured values show good reproducibility, giving deviations of less than 7%.

In all three experiments, approximately 110% of the particles were retrieved when determining the 100% value although the result of the validation of drying process was considered.

These particles (10%) must be considered as error of determination. As the difference is far below the 20% criterion of the particle size distribution following OECD 110, this is considered as uncritical.

The graphs of the particle size distribution show that a considerable aliquot of particles smaller than 10μm (thoracic fraction) and few particles smaller than 4 μm (alveolar fraction) are present in the test item Calciumthioglycolate x 3 H₂O (mercaptoacetic acid calcium compound).

No observations were made which might cause doubts concerning the validity of the study outcome. The result of the test is considered valid.

Description of key information

Partice size distribution was determined acc ISO 13327-2 (OECD 110) fixed pipette method.

Additional information

Stokes-diameter (Xn)in µm	Mass under particle size Exp. 1	Mass under particle size Exp. 2	Mass under particle size Exp. 3	Mass under particle size Mean	Difference	Mass under particle size Mean	Mass under particle size Mean
	meas. part	meas. part	meas. part	meas. part		total test item	total test item (incl. recovery rate)
105.16	98.84%	97.65%	99.42%	98.63%	1.77%	83.55%	108.54%
61.92	94.77%	94.71%	97.66%	95.71%	2.95%	81.07%	105.32%
43.04	87.21%	91.18%	93.57%	90.65%	6.36%	76.78%	99.74%
34.53	79.65%	82.94%	85.38%	82.66%	5.73%	70.01%	90.95%
26.26	65.12%	67.06%	67.84%	66.67%	2.72%	56.47%	73.36%
20.37	50.00%	50.00%	51.46%	50.49%	1.46%	42.76%	55.56%
14.12	29.07%	28.24%	28.65%	28.65%	0.83%	24.27%	31.53%
9.78	16.28%	14.71%	16.37%	15.79%	1.67%	13.37%	17.37%
6.77	7.56%	6.47%	9.94%	7.99%	3.47%	6.77%	8.79%
4.68	5.81%	5.29%	7.60%	6.24%	2.31%	5.28%	6.86%