Cholesterol

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Well documented publication. The study was intended to report on the detailed fatty acid and sterol composition of raw and treated sewages from different treatment plants. The publication gives important information on cholesterol contents in influent and effluent of actual sewage treatment plants.

Data source

Reference

Reference Type:

publication

Title:

Fatty acids and sterols in domestic wastewaters

Author:

Quemeneur, M. and Marty, Y.

Bibliographic source:

Wat. Res. Vol.28, No5, pp.1217-1226, 1994

Materials and methods

Principles of method if other than guideline:

Raw and treated sewage from physical-chemical and biological wasterwater treatment plants were analyzed for fatty acids and sterols by HPLC and GC.

Test material

Test material information

Constituent 1

Reference substance name:

Cholesterol

EC Number:

200-353-2

EC Name:

Cholesterol

Cas Number:

57-88-5

Molecular formula:

C27H46O

IUPAC Name:

cholest-5-en-3-ol

Results and discussion

Details on results:

- Characterization of the raw sewage showed that most (80 -95%) of the fatty acids and sterols were in the particulate fraction. Cholesterol represented 23 -38% of the particulate sterols. In the dissolved fraction of the raw sewage, the percentage of cholesterol was 42 -62%.
- The lipid composition of raw sewage is dominated by four fatty acids: 18:1 (n-9), 16:0, 18:0 and 18:2 (n-6) and two sterols: coprostanol and cholesterol.
- The investigations in the three plants showed that raw sewage constitutes a daily input of 4 -8 g of fatty acids and 0.5 -0.6 g of sterols per capita. For treated wastewaters, the values range from 0.2 to 4 g of fatty acids and from 0.01 to 0.2 g of sterols per capita.

Applicant's summary and conclusion

Conclusions:

Based on the fact that most sterols (80-95%) are in the particulate fraction and cholesterol constitutes between 23 and 38% of the particulate sterols, the daily input in raw sewage of 0.5-0.6 g of sterols per capita can be recalculated to a daily input of approximately 0.09-0.22 g cholesterol per capita.
Together with the amount of cholesterol in the soluble fraction of raw sewage, the daily input in raw sewage of 0.5-0.6 g of sterols per capita constitutes between 0.1 and 0.3 g cholesterol.