Number

267-EN

Section

General Section

Use

Abstract

Filter packs made from crushed recycled glass can replace filters made of crystalline silica- containing materials, such as sand or zeolites. They provide good filtration quality and economic advantages.

Substituted substances

Alternative Substances

Reliability of information

Evidence of implementation: there is evidence that the solution was implemented and in use at time of publication

Reason substitution

CMR

Hazard Assessment

Substance to be substituted: Quartz (crystalline silica) is the main constituent of sand and is also contained in high quantities in zeolites. Zeolites has no harmonised classification according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). But the included quartz is a group 1 carcinogen (IARC) as listed in the Substance Database according to SUBSPORTplus Screening Criteria (SDSC). However, it has a recognised carcinogenic effect, which is recorded in the TRGS 900 implementing an EU limit BOELV: quartz (alveolar): 0.1 mg/m³ (2004/37/EC) and in Germany. 0.05 mg/m³. Alternative substance: Crushed glass with size 0.3-1 mm used to replace sand or zeolite filters

Description of Substitution

Sand and zeolite water filters are affordable and easy to run so they have been used for swimming-pools and for other water treatment facilities. Sand is mainly composed of crystalline silica, while zeolites may have a 10-15% content of this hazardous form of silica. Crystalline silica (or quartz) is a recognised human carcinogen according to IARC and may cause silicosis, a very severe respiratoryillness. Though the risk in not high for the users of filters, exposure to crystalline silica is higher and consequences may be severe for those that produce or maintain the filters. Glass contains another form of silica amorphous or non- crystalline- that is less hazardous than quartz. Recycled, crushed glass with size 0.3-1 mm, can be used to replace sand or zeolite filters. The producer recommends the filter for swimming pools, but also for industrial applications. Beside the health issues, the glass filter has other advantages, compared to sand and zeolites, as stated by the producer: -it consumes less backwash water; -particle size removal is similar to that of zeolites ( 2-5 microns) and better than for sand ( 50-100 microns) -is less likely to block or channel -it lasts longer -it provides better turbidity removal.

Case/substitution evaluation

The substitution is easy to implement. Glass does not contain hazardous crystalline silica. The fact that is 100% recycled makes it cheaper and expands the useful life of glass. A limitation in some applications is that glass does not have the ion exchange properties of natural or synthetic zeolites, though a feeble negative surface charge may attract positive ions. However, this quality of zeolites needs to be maintained by using regenerating solutions, which may be hazardous and rise costs . Zeolites that enter the general sewage system, may impact negatively on the water treatment processes in municipal stations due to their ion-exchanging properties and their very big specific surface area. These hazards are not characteristic for glass.

State of implementation

In use

Availability of Alternative

Alternative available on the market.

Producer/Provider

www.ecosmarte.com and www.glasspackfilter.com

Type of information supplier

Producer / distributor

Contact

www.ecosmarte.com and www.glasspackfilter.com

Type of publication and availability

Internet presentation, freely available

Publication source: author, company, institute, year

The description is based on the information published by the producer ECOsmarte Planet Friendly Inc, on its website, in 2007.

Publication source

Type of publication and availability

http://www.glasspackfilter.com/articles/glass_filtration_media-2.pdf

Date, reviewed

November 26, 2021