Environmental Health & Safety
The following information gives an overview on environmental, health and safety aspects of Carbon Black.
Carbon Black is engineered material, primarily composed of elemental carbon. It is obtained from the partial combustion or thermal decomposition of hydrocarbons and exist as aggregates of aciniform morphology which are composed of spherical colloidal particles.
The aggregates are loosely held together by weaker forces forming larger entities called agglomerates which is the form in which Carbon Black is placed on the market. Depending on end-user industry i.e. rubber and tire or pigment industry, Carbon Black can be categorized in Rubber Blacks and Specialty Carbon Blacks, respectively.
In decades of Carbon Black production and processing using a variety of methods, no significant hazardous effects have so far been registered. Details on the individual measures regarding safe handling of Carbon Blacks are described in the relevant safety data sheets.
In end-use products, such as toners, plastics, and surface coatings, Carbon Black is matrix-bound, and – according to our own surveys as well as according to neutral third party surveys – does not pose an exposure risk to end-users.
According to the National Toxicology Program (NTP/USA) as well as European (excluding Denmark) and American legislation regarding chemicals (OSHA), Rubber Blacks and Specialty Carbon Blacks do not exhibit a mutagenic, teratogenic or carcinogenic potential.
Under normal application conditions Carbon Blacks do not display any explosive potential. However, in the presence of significant igniting energy, e. g., a welding torch, Carbon Black/air mixtures may explode. For this reason, Carbon Black sources must be removed or hermetically sealed prior to equipment repairs in the vicinity of welding operations or equipment generating high operating temperatures. Carbon monoxide build-up is possible in sealed containers such as silos or in unventilated storage facilities. Here, too, ignition sources should be removed and self-contained air supply systems should be used. Carbon Blacks should be stored under dry conditions. In application or use scenarios where the “general dust limit value” of 10 mg/m3 for the inhalable dust fraction and 3 mg/m3 for the alveolar dust fraction (in Germany) or a concentration of 3.5 mg/m3 for total dust (USA and most European countries) is exceeded, an air suction should be in operation or personnel should be required to wear a protective dust mask. Spilled material can be collected to avoid dust build-up, stored in appropriate containers or burned in appropriate firing facilities.
Environment: Ecotoxicology
Carbon Black is an inorganic water insoluble substance. For this reason its bioavailability for aquatic organisms is very low. In acute tests according to OECD test guidelines with fish, daphnia and algae nominal concentrations of 1000 mg/l showed no effects. Based on the physicochemical and acute toxicological data no chronic effects and no bioaccumulation are to be expected in aquatic organisms. The general guidelines for the examination of the biodegradability of substances (OECD, EEC-guidelines) can be used only for organic substances and thus do not apply to Carbon Black. Carbon Black is an inert inorganic substance with the structural formula “C” and is not biodegradable by microorganisms. The German commission for the evaluation of water polluting substances has classified Carbon Black as a “not water endangering” substance (KBwS-No: 1742).
