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What about work in the lab in case of pregnancy?

Restrictions according to § 5 of the "Mutterschutzrichtlinienverordnung":

  • Pregnant women must not work with carcinogenic, reproductive toxic or mutagenic compounds. Working with fatal or toxic compounds or with compounds which may cause chronic diseases is only allowed within the limit values. Pregnant women may work with carcinogenic, reproductive toxic or mutagenic compounds, if they are not exposed to them. An exposure has to be assumed even if anybody else in the same room is opening a bottle with a relevant compound.
  • Nursing mothers may work with carcinogenic, reproductive toxic, mutagenic, fatal or toxic compounds or with compounds which may cause chronic diseases only within the limit values.
  • Women of reproductive age may work with compounds containing lead or mercury alkyls only within the limit values.

Limit values:

  • Occupational exposure limit (air concentration) according to TRGS 900.
  • Biological limit value (generally concentration in blood or urine) according to TRGS 903.

According to § 4 of the "Mutterschutzrichtlinienverordnung" the empoyer has to prevent pregnant or nursing women from any risk. It is well known that conditions which are risk-free for "everybody" sometimes may not be applied for pregnant women (think of "contergan"). Therefore you will find in the TRGS 900 a column with code letters where "Y" means that for pregnant women there is still a risk even within the limit values and "Z" means that the risk does not change for pregnant women. If there are no data (legal restrictions, limit values) it is the job of the employer to evaluate the risk.

It has to be legally stated that the reglementations do not only enclude employees but also students. The inclusion of the students is found in the BGI/GUV-I 8666 ("Tätigkeiten mit Gefahrstoffen in Hochschulen").

According to the Verordnung zum Schutze der Mütter am Arbeitsplatz pregnant women must not be exposed to compounds which are carcinogenic, mutagenic or toxic for reproduction. It is generally stated by the hazard phrases shown on the label, if a compound has one or more of these properties:

Carcinogenic compounds:


R 45 May cause cancer.
R 49 May cause cancer by inhalation.

H-Phrases (CLP) H350 May cause cancer.
H350i May cause cancer by inhalation.

Mutagenic compounds

R-Phrases R 46 May cause inheritable genetic damage.
H-Phrases (CLP) H340 May cause genetic defects.

Compounds which are toxic for reproduction

R-Phrases R 60 May impair fertility.
R 61 May cause harm to the unborn child.
H-Phrases (CLP) H360 May damage fertility or the unborn child.
H360F May damage fertility.
H360D May damage the unborn child.

It may be that a compound is only suspected to have these properties. Then it is the job of the employer (= Group head) to evaluate the facts according to § 4 of the Verordnung zum Schutze der Mütter am Arbeitsplatz. Suspected properties are stated on the label as follows:

R-Prases R 40 Limited evidence of a carcinogenic effect.
R 68 Possible risk of irreversible effects.
R 62 Possible risk of impaired fertility.
R 63 Possible risk of harm to the unborn child.
H-Phrases (CLP) H351 Suspected of causing cancer.
H341 Suspected of causing genetic defects.
H361f Suspected of damaging fertility.
H361d Suspected of damaging the unborn child.

CMR-compounds where the properties are not found on the label

Unfortunately it may be the case that the hazardous potential is not found on the label. This is not only true, if the potential is still unknown but may also happen, if the potential is discussed controversial. The background is that approximately 3000 compounds have a mandatory harmonised EU-classification. It may happen that a compund for example has an EU-classification to be suspected to be effective, whereas the German Ausschuss für Gefahrstoffe did classify it as proven to be effective. Then the compound is elsewhere suspected and in Germany proven to be active. The problem is that the labelling of compounds with a harmonised classification must not be changed by national organisations.

In this case you will not see any information on the label that a compound for example has to be considered as carcinogenic!

The only thing the Ausschuss für Gefahrstoffe can do is to publish his classifications with a legally binding in the TRGS 905.

To make sure if a compound in Germany is classified for example to be carcingenic also the TRGS 905 has to be considered.

This is not as scary as it seems since in the TRGS 905 there are only very few compounds with relevance in our labs. The most important compound is probably chloroform.

A complete investigation if a compound has a cmr-potential should include to search the "MAK-Collektion" of the DFG-Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe. Not all scientific data collected by this commission find their way via the Ausschuss für Gefahrstoffe to legal force. Therefore the data of the "MAK-Kollektion" are only an information. But this information is very helpful for an assessment of the workplace according to § 4 of the Verordnung zum Schutze der Mütter am Arbeitsplatz. For a given compound you may search the findings of the DFG-Senatskommission also in the GESTIS-Database (Chapter "Regulations" -> "Recommendations of MAK-Commission").

Since there is often a relation between the molecular structure and the carcinogenic potential, data bases with structure features suspected to be carcinogenic have been created. On searching theses data bases you may get a prediction of the carcinogenic property of an unknown compound. A free online tool is the Osiris Property Explorer.

Consultation in case of pregnancy is provided by the company physician.