Standards Development

Scope

This document specifies test methods and evaluation criteria by addressing potential ecotoxicological adverse effects on marine organisms. Adverse effects on marine species may be caused by plastic materials and degradation products resulting from the decomposition of biodegradable plastic materials that are intentionally or unintentionally disposed to marine environment.

The ecotoxicity testing scheme covers marine organisms from three trophic levels:

- toxicity to marine microorganisms

- toxicity to marine algae

- toxicity to marine invertebrate. Toxicity to marine fish is not considered due to animal welfare considerations.

This document is not suitable for the assessment of adverse effects caused by solid, nonbiodegradable plastic materials such as microplastics.

Purpose

As a result of irresponsible human behavior combined with poor waste management a continuous increase of marine litter in the marine environment is expected. Even the uncontrolled dispersion of biodegradable plastics in natural environments including marine habitats is not desirable. The biodegradability of plastic products cannot be considered as an excuse to spread wastes in marine areas that should be recovered and recycled. In addition, it is well known and documented that marine litter can pose risks and a negative impact on living marine organism and on human beings.

The impact and strength of adverse effects is linked to the fate of plastic materials exposed to the marine environment. Therefore, test methods to measure the level of biodegradation and disintegration of plastic materials in different marine habitats have been established by ISO/TC 61/SC 14 in recent years in order to better characterize the degradation of plastics in these very particular environments:

- ISO standards like ISO 18830 (or ISO 19679), ISO 22404 and ISO/DIS 23977-1 (or ISO/DIS 23977-2) are suited to investigate the biodegradation of plastic materials exposed to aerobic, coastal marine habitats such as sublittoral, eulittoral (sediment) and pelagic zones, respectively.

- The ISO standard specification ISO 22403 specifies test methods and requirements to assess the intrinsic biodegradability of materials exposed to marine inocula under mesophilic aerobic laboratory conditions.

- The ISO standard ISO 22766 describes methods for the determination of the degree of disintegration of biodegradable plastic materials exposed to sublittoral and eulittoral habitats under real field conditions.

Beside data on the biodegradability of plastics materials, tests on ecotoxicological effects to marine organisms are necessary to enable developer and manufacturer of materials to evaluate and to exclude negative effects against marine organisms. In addition, in combination with data on biodegradability, data on ecotoxicological effects may be used for e.g. risk assessment purposes.

The proposal specifies test methods and requirements for assessing potential adverse effects on different marine organisms caused by plastic materials and residues as intermediates (degradation products) resulting from the decomposition of materials that are intentionally or unintentionally disposed to marine areas.

Comprehensive ecotoxicity testing schemes and evaluation criteria are already part of ISO standard specifications like ISO/DIS 17088 and ISO/DIS 23517-1. The scheme and criteria given in ISO/CD 23517-1 are equivalent to the requirements specified in the CEN-standard EN 17033. The CENstandard prEN 17427 on carrier bags suitable for treatment in well-managed home composting installations includes an ecotoxicity testing scheme that follows the same basic principles as given in above mentioned ISO- and EN-standard specifications: adverse effects are assessed based on results from three tests covering organisms representing different trophic levels.

This proposal is aiming to provide a suitable ecotoxicity testing scheme for marine organisms and evaluation criteria following the basic principles laid down in above mentioned ISO-/CEN-standard specifications.