Navigating the Shift: NPEO Replacement in Surfactants

Alkylphenol ethoxylates, In the realm of industrial and household cleaning products, surfactants play a pivotal role. These compounds, known for their ability to reduce surface tension between liquids, or a liquid and a solid, are essential in detergents, emulsifiers, foaming agents, and dispersants. However, one of the traditionally used surfactants, nonylphenol ethoxylates (NPEOs), has come under scrutiny due to its environmental impact. As a result, the industry is witnessing a significant shift towards NPEO replacements. This article explores the reasons behind this transition and the alternatives emerging in the market.

The Environmental Concern: Why Replace NPEOs?

Nonylphenol ethoxylates are effective surfactants, widely used for decades due to their performance and cost-effectiveness. However, their environmental and health implications have driven the push for alternatives. Key concerns include:

Persistence and Bioaccumulation: NPEOs degrade into nonylphenol (NP), a compound that is both persistent in the environment and bioaccumulative. This means it can accumulate in the tissues of organisms, moving up the food chain and posing risks to wildlife and humans.
Endocrine Disruption: NP has been identified as an endocrine disruptor, interfering with the hormonal systems of organisms. This disruption can lead to reproductive and developmental problems in wildlife, particularly aquatic species.
Regulatory Pressure: Regulatory bodies across the globe, including the European Union and the United States Environmental Protection Agency (EPA), have enacted strict regulations limiting the use of NPEOs. For instance, the EU’s REACH regulation (Registration, Evaluation, Authorisation and Restriction of Chemicals) has placed severe restrictions on the use of NP and NPEOs.

Potential health hazards

If wash off let to the environment, it may cause eutrophication in river beds.

NPEO is termed to be dangerous to aquatic life.
It is non-biodegradable.
If NPEOs and OPEOs are released to the environment, they can be degraded back to NPs and OPs, which are toxic to aquatic life, persistent in the environment and can be bioaccumulated in body tissue. They are similar to natural estrogen hormones and can disrupt sexual development in some organisms, e.g. causing feminization of fish.

APEOs are present as residues in textiles and leather. 90% of the produced APEO are in fact NPEO.

Related legislation (non-exhaustive)

European Union: REACH Annex XVII, entry 46a (will apply from 3rd February 2021)
Taiwan: CNS 15290 Safety of Textiles

Maximum limit (non-exhaustive)

NPEO: 0.01% by weight for textile articles expected to be washed in water during their normal lifecycle.
NP and NPEO: 1000 mg/kg (children’s clothing)

Alternatives to NPEOs: Emerging Replacements

Given these concerns, the industry has been innovating to find suitable replacements for NPEOs that offer similar performance without the associated environmental risks. Some promising alternatives include:

Alcohol Ethoxylates (AEs): These surfactants are gaining popularity due to their biodegradability and lower toxicity. Derived from renewable resources like plant-based alcohols, AEs offer comparable cleaning and emulsifying properties to NPEOs.
Alkyl Polyglucosides (APGs): Made from natural sugars and fatty alcohols, APGs are both biodegradable and non-toxic. Their mild nature makes them suitable for personal care products as well as household cleaners.
Methyl Ester Ethoxylates (MEE): These surfactants are derived from natural oils such as soybean or palm oil. They are biodegradable and offer good cleaning properties, making them a viable replacement in many applications.
Sorbitan Esters and Alkoxylated Fatty Acids: These compounds are used in various industrial and cosmetic applications. They provide good emulsifying properties and are considered environmentally friendly.
Silicone-based Surfactants: While more expensive, silicone-based surfactants offer excellent performance in specific applications such as defoaming agents and are known for their low toxicity and environmental impact.

Challenges in Transitioning

While the benefits of moving away from NPEOs are clear, the transition is not without its challenges:

Performance Matching: Ensuring that alternatives match or exceed the performance of NPEOs in various applications is critical. This requires significant research and testing.
Cost Implications: Some alternatives, particularly those derived from renewable resources or advanced synthetic processes, can be more expensive. Balancing cost with environmental benefits is a key consideration.
Supply Chain Adjustments: Switching to new raw materials and suppliers involves adjustments in the supply chain, which can be complex and time-consuming.
Regulatory Hurdles: Ensuring that new surfactants meet all regulatory requirements across different regions can be a challenging process.

The Future of Surfactants

The replacement of NPEOs marks a significant step towards more sustainable and environmentally friendly surfactants. As research and development continue, it is likely that more efficient and cost-effective alternatives will emerge, further driving the shift away from harmful substances. The industry’s commitment to sustainability, coupled with regulatory pressures, ensures that the move towards safer surfactants will continue to gain momentum.

In conclusion, the transition from NPEOs to safer alternatives is not just a regulatory necessity but a moral imperative to protect our environment and health. While challenges exist, the future of surfactants looks promising, with innovation paving the way for products that are both effective and eco-friendly.

NPE replacements by LANKEM

Typically, NP20-40 are used as the secondary stabiliser

Alternatives