Phthalates
Phthalates are a group of chemical compounds used as plasticisers in plastic, particularly in PVC. They are also found in a wide range of other products, including paints, adhesives, sealants, floor coverings and certain cosmetics. What phthalates have in common is that they are not chemically bonded to the materials they are added to — which means they can leach into the surrounding environment over time.
Environmental and health impact
Phthalates are classified as endocrine-disrupting substances and pose risks to both humans and aquatic organisms. They can interfere with the hormonal systems of animals and people even at low concentrations, and certain phthalates are classified as reproductive toxins.
In aquatic environments, phthalates can:
- Affect the reproductive capacity of fish and other aquatic organisms
- Bioaccumulate in the food chain, reaching high concentrations in predators
- Persist for long periods in sediment and water, as they are resistant to natural breakdown
Where do they come from?
Phthalates reach aquatic environments through several pathways. On construction sites and industrial plots, old flooring, pipes and sealants can contain high concentrations of phthalates that are released when materials are demolished or excavated. Leachate from landfills and contaminated land is another common source. Stormwater runoff from hard surfaces can also carry phthalates from the degradation of older plastic-containing materials.
Treatment
Phthalates are organic compounds that require a different treatment approach than metals or particulates. Although they are poorly soluble in water, they can still occur at concentrations low enough to evade conventional methods yet high enough to cause environmental harm. Neither sedimentation nor simple flocculation is sufficient to remove them effectively.
Swedish Hydro Solutions primarily uses two methods, depending on the situation and concentration levels:
- BioMedia® filters — a biologically active filter medium in which microorganisms break down organic contaminants such as phthalates. This method is effective in continuous-flow applications and works particularly well when phthalates are present alongside other organic pollutants.
- Carbon filters — activated carbon has a large surface area that efficiently binds organic compounds. Carbon filters are often used as a polishing step to achieve very low residual concentrations, or as the primary method in shorter projects with stringent treatment requirements.
In some cases, the two methods are combined to achieve the best possible results.
Further reading
BioMedia® filters
Gravity filters with BioMedia® effectively remove heavy metals and reduce a wide range of organic contaminants, from oil‑based to chlorinated.
Bo Altenstam
Bo Altenstam AB in Hörby is a licensed waste operator in Sweden handling cable recycling and various types of metal waste.
Do you need more info?
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