Substances in this group have been shown to have estrogenic activity in several assays, and minor perturbations in the reproductive system of offspring after exposure over several generations have been reported. Feminisation of male fish has also been observed.
Many alkylphenols are toxic or highly toxic to aquatic organisms and may cause long-term adverse effects. The most toxic are those with a large alkyl chain.
Function and use
Alkylphenols and their ethoxylates consist of one hydrophilic and one lipophilic part of the molecule, giving them the properties they are commonly used for. Most of them belong to the group of less-foaming, non-ionic detergents.
Other compounds in this group are polyalkylated phenols such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which have antioxidant properties.
Areas of application
Alkylphenols are used extensively as precursors to detergents, as additives for fuels and lubricants and as building block chemicals for fragrances, thermoplastic elastomers and fire-retardant materials. Alkylphenol residues are found in alkylphenolic resins and thus alkylphenols are also found in products that contain alkylphenolic resin, such as tyres, adhesives, carbonless copy paper and high-performance rubber products.
Alkylphenol ethoxylates are surface-active substances that are used in cleaning and laundry products, wetting agents, softeners and spinning oils (yarn and fabric), and emulsifier/dispersing agents.
Other alkylated phenols like BHT and BHA may be used as additives in food, cosmetics or in other materials for controlling free radicals.
There are varying degrees of restriction for this group of compounds. Some of them are suspected endocrine disruptors and have commonly, due to this property, been included in the REACH Candidate List or restricted in REACH annex XIV or in annex XVII.
Ethanolic extracts of canola meal have shown antioxidative activity like commonly used synthetic antioxidants, such as BHA and BHT.
The technology of using anionic surfactants for general cleaning, dishwashing and laundry can be improved in order to achieve similar effect as with APEOs (alkylphenol ethoxylates).
Examples of alternatives have been identified by the US Environmental Protection Agency Design for the Environment Program:
C9-11 alcohols, ethoxylated (6EO)
C12-15 alcohols, ethoxylated (9EO)
Oxirane, methyl-, polymer with oxirane, mono (2-ethylhexyl ether) Ecosurf EH-9
Glucopyranose, oligomeric, decyl octyl glycosides
Benzenesulfonic acid, C10-13-alkyl derivs., sodium salt
Sodium lauryl sulfate
Polyoxy (1,2-ethanediyl), alpha-sulfo-omegadodecyloxy-, sodium salt