2-(2-methoxyethoxy)ethanol

Specific investigations: other studies

Administrative data

Endpoint:

endocrine system modulation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Data source

Reference

Reference 1

Reference Type:

publication

Title:

Endocrine-disrupting activity of hydraulic fracturing chemicals and adverse health outcomes after prenatal exposure in male mice

Author:

Kassotis CD, Klemp KC, Vu DC, Chung-Ho L, Meng CX, Besch-Willliford CL, Pinatti L, Zoeller T, Drobnis EZ, Balise VD, Isiguzo CJ, Williams MA, Tillit DE, Nagel SC.

Year:

2015

Bibliographic source:

Endocrinology 156(12), 4458-73

Reference 2

Reference Type:

publication

Title:

Estrogen and Androgen Receptor Activities of Hydraulic Fracturing Chemicals and Surface and Ground Water in a Drilling-Dense Region.

Author:

Kassotis CD, Tillitt DE, Davis JW, Hormann AM, Nagel SC

Year:

2014

Bibliographic source:

Endocrinology, 155(3):897–90

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

Measurement of potential for endocrine disrupting activity for five nuclear receptors using a reporter gene assay in human endometrial cancer cells. The hypothesis was that the chemicals used in oil and natural gas operations (including this substance) would exhibit antagonist activities for nuclear hormone receptors.

GLP compliance:

no

Type of method:

in vitro

Endpoint addressed:

toxicity to reproduction / fertility

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-methoxyethoxy)ethanol

EC Number:

203-906-6

EC Name:

2-(2-methoxyethoxy)ethanol

Cas Number:

111-77-3

Molecular formula:

C5H12O3

IUPAC Name:

2-(2-methoxyethoxy)ethanol

Specific details on test material used for the study:

Source: Sigma Aldrich. No purity information.

Results and discussion

Any other information on results incl. tables

The results as interpreted from the graphical information presented are as follows:

	POSITIVE CONTROL			DEGME
Concentrations in molar	EC10	EC50	EC50/EC10	EC10	EC50	EC50/EC10
Anti-oestrogenic	3x10^-11	3x10^-10	10	1x10^-7	not reached	>1000
Anti-progestogenic	8x10^-10	5x10^-9	6.3	5x10^-5	not reached	>1000
Anti-androgenic	2x10^-7	2x10^-6	10	4x10^-6	not reached	>25
Anti-androgenic*	9x10^-8	2x10^-6	22	2x10^-6	~1x10^-4	~50
Anti-glucocorticogenic	2x10^-10	7x10^-9	35	5x10^-5	not reached
Anti-thyroidogenic	1x10^-7	1x10^-6	10	No effects seen

*HepG-2 liver cancer cell line. All others Ishikawa cell lines

For DEGME, the EC50 was not seen for most end points up to the maximum tested concentration.

Applicant's summary and conclusion

Conclusions:

For a number of reasons, it is difficult to draw conclusions from this study. There are a number of shortcomings, which may be due to deficiencies in the reporting rather than inherent deficiencies in the method, although it is not a validated one, but it means that these results cannot be relied upon as evidence of endocrine effects.

Executive summary:

In an in vitro study using cells transfected with gene reporters, 24 chemicals found in fracking formulations were individually assessed for possible endocrine antagonism effects. DEGME was found to have some activity towards androgen, estrogen, progesterone and thyroid receptors but not thyroid. However, the effects were weak and the dose response curves shallow. IC50 values were not reached for the any of the tests using the Ishikawa cell line up to the maximum tested concentration of 0.1mM and only just seen (IC50 ~0.1mM) for the anti-androgenic activity of the reporter transfected into HepG-2 liver cancer cell line. Overall, the reliability of this study as reported cannot be assessed for a number of reasons, but particularly because no information is provided on the number of replicates or concentrations tested and a complete lack of statistical information.