Biopolymer as alternative to petroleum based soil modifiers like polyacrylamide or bitumen.

Number

257-EN

Section

General Section

Use

Sector

Building and construction work
Other

Function

Plating agent

Process

Manual activities involving hand contact

Product category

other

Application

Soil modification

Abstract

Soil modification for civil or military applications can be done with a biopolymer instead of using petroleum based chemicals like polyacrylamide or asphalt emulsions.

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

Bitumen

CAS No. 8052-42-4 EC No. 232-490-9 Index No.

Chemical group

Hydrocarbons

Other adverse effects

The substance is: 2B carcinogen (IARC) as listed in the Substance Database according to SUBSPORT Screening Criteria (SDSC).

Reliability of information

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

Reason substitution

CMR

Other type of alternative

Modified biopolymer obtained from Rhizobium tropici microorganisms.

Hazard Assessment

Substance to be substituted: Polyacrylamide is not listed in the SUBSPORTplus Database and has no harmonised classification according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). Bitumen is possibly carcinogenic to humans (Group 2B), according to the IARC Monographs. It fulfils the criteria to be listed in the Substance Database according to SUBSPORTplus Screening Criteria (SDSC). Alternative substance: The alternative biopolymer is no listed in the SUBSPORTplus database for substances of concern. It occurs in nature and is not known by now to have adverse health effects.

Description of Substitution

Soil modification is used in military applications such as improving slope stability or preventing dust emissions and related problems like air pollution, reduced visibility and increased abrasion of equipment due to airborne particles. A project funded by the US Security, Technology Certification Programme (ESTCP ER 0920) obtained and tested a biopolymer that canreplace oil-based polymers in soil modification applications. The polymer is obtained from Rhizobium tropici, a known symbiotic nodulator for vegetables: a bacterium that lives in symbiosis with leguminous plants developing nodules that are beneficial for the plant aiding it in nutrient absorption and nutrient fixation. Obtaining the biopolymer does not involve any seriously hazardous chemicals. Ethanol is used to separate the biopolymer and it is the cost driver of the process along with electricity for ethanol recovery and distillation. The polymer can be modified with sodium chloride, then separated and dried, which makes it more easily transportable. It can be applied dried or wet.

Case/substitution evaluation

The substitution is easy to implement. The technology mimics the activity of extracellular polymeric substances (EPS) that are present in nature and have not been reported as having negative effects on soil or plants. On the contrary they aid in water and nutrient retention. The substitution prevents the use of a chemical that is not toxic in itself but it is made of and it decomposes into a monomer of high concern (acrylamide).

State of implementation

Pilot study

Date and place of implementation

Presentation published in 2010, in USA

Availability ofAlternative

At the date of publication  (2010) the alternative was used in pilot study, with promising results.

Producer/Provider

ERDC-ENvironmental Laboratory Environment, of the US Army Corps of Engineers, https://www.erdc.usace.army.mil/Locations/EL/

Type of information supplier

Research

Contact

ERDC-ENvironmental Laboratory Environment, of the US Army Corps of Engineers, https://www.erdc.usace.army.mil/Locations/EL/

Type of publication and availability

Brochure, freely available on internet

Publication source: author, company, institute, year

The presentation is based on the brochure Modified Biopolymers as an Alternative to Petroleum-based Polymers for Soil Modification, by  Chris Griggs of ERDC-ENvironmental Laboratory Environment, published on the website of the National Defense Industrial Association

Date, reviewed

November 26, 2021