Analytical method for the determination of 4-chloroaniline

Translation of DGUV Information 213-552 (former BGI 505- or ZH1/120.)

CAS Number: 106-47-8

Synonym: p-Chloroaniline

Method 02 – GC-MS

Sampling is carried out with a pump and adsorption on two acid impregnated filter. Analysis is performed by gas chromatography after desorption.

This method involves the use of personal or stationary sampling procedures to determine the mean concentration of 4-chloroaniline in the work area over the sampling period.

Principle

A pump is used to draw a defined volume of air through two acid-impregnated filters.  4-Chloroaniline is then desorbed from the filter using a mixture of acetonitrile and ammonia solution and determined by mass spectrometry after separation by gas chromatography (GC-MS).

Limit of quantification (LOQ)

Absolute: 0.22 ng, 0.89 µg per sample carrier.

Relative: 0.0037 mg/m³ for an air sample volume of 240 l, 4 ml of desorption solution and an injection volume of 1 μl.

Issue

February 2023

The complete measuring method is available in the ZB Med: p-Chloroaniline – Determination of p-chloroaniline in workplace air using gas chromatography (GC-MS) (Air Monitoring Method. The MAK Collection for Occupational Health and Safety, 2024, Volume 9, No. 3).

Method 01 – HPLC – withdrawn

Sampling with a pump and adsorption on impregnated silica gel, high performance liquid chromatography (HPLC) after desorption.

This method permits the determination of 4-chloroaniline concentrations in working areas averaged over the sampling time after personal or stationary sampling.

Principle

With a pump a measured air volume is drawn through a sampling tube containing silica gel impregnated with hydrochloric acid. The 4-chloroaniline is bound as a hydrochloride. At room temperature 4-chloroaniline is a solid substance. Therefore, sampling has to be carried out as stipulated in the definition of inspiration rate.

A mixture of methanol and aqueous ammonia is used for desorption. The amine is determined analytically by HPLC.

Limit of quantification (LOQ)

Absolute: 1.5 ng p-chloroaniline.

Relative: 0.004 mg/m³ 4-chloroaniline for 120 L air sample. This corresponds to 0.45 μg 4-chloroaniline in the sample for 3 mL eluate and 10 μL injection volume.

Issue

May 1993

Withdrawn

September 2014

The complete measuring method is available in the Wiley Online Library: Method for the determination of p-chloroaniline (Air Monitoring Methods, 1999).