Starch hydrogels as alternative to polyacrylamide in soil treatment

Number

263-EN

Section

General Section

Use

Sector

Building and construction work
Other

Function

Other

Process

Other

Product category

washing ad cleaning products

Application

Polyacrylamide in soil treatment

Abstract

Polyacrylamide used for soil treatment is made from a hazardous monomer – and it may decompose to this monomer in the environment.Polyacrylamide can be replaced by other starch hydrogels.

Substituted substances

Polyacrylamide

CAS No. 9003-05-8 EC No. Index No.

Chemical group

Polymers

Other adverse effects

In the environment it may degrade to acrylamide (CAS 79-06-1), a carcinogen and mutagen 1B and skin sensitiser according to EU harmonized classification, also classified as  probably carcinogenic according to IARC (group 2A) and neurotoxicant ( V

Alternative Substances

Starch

CAS No. 9005-25-8 EC No. 232-679-6 Index No.

Chemical group

Carbohydrates

Reliability of information

Internet information: data are from an internet document and only a basic and partial evaluation could be performed

Reason substitution

CMR

Hazard Assessment

Substance to be substituted: Polyacrylamideis not listed in the SUBSPORTplus Database and has no harmonised classification according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). Alternative substance: Starch is not hazardous and can be obtained from natural renewable sources.

Description of Substitution

Polyacrylamide is used as hydrogel for soil treatment in agriculture and other civilian and military applications. It helps stabilise the soil and improves retention of water but also of other chemicals like pesticides or fertilisers. It is used as additive in irrigation systems but is also available in commercial products for private gardening. Polyacrylamide is medium stable and is not considered toxic in itself. However, in the environment it decomposes to its monomer acrylamide, which is a known carcinogen. The presence of some substances in fertilisers or pesticides may enhance polyacrylamide e decomposition. Starch based hydrogels or other bio-based polymers can be used as alternatives. They are not toxic as monomers or polymers and do not generate hazardous pollutants when decomposing. They are however shorter-lived compared to polyacrylamide.

Case/substitution evaluation

The substitution prevents the use of a chemical that is not toxic in itself but it decomposes into pollutants of high concern (acrylamide). Substitution is easy to implement both at large scale soil treatment and at household level. Because starch hydrogel last for shorter time the treatment may need to be repeated more often and end up being more expensive.

State of implementation

In use

Availability ofAlternative

Alternative available on the market

Type of information supplier

Research

Contact

Puyallup Research & Extension Center of Washington State University, http://www.puyallup.wsu.edu/

Type of publication and availability

Internet information, freely available

Publication source: author, company, institute, year

Super-absorbent water crystals-miracle, myth or marketing', by Linda Chalker-Scott, PhD, Puyallup Research & Extension Center of Washington State UniversityLinda Chalker-Scott, Horticultural Myths https://puyallup.wsu.edu/lcs/

Publication source

Type of publication and availability

https://puyallup.wsu.edu/wp-content/uploads/sites/403/2015/03/hydrogels-3.pdf

Date, reviewed

November 26, 2021