RECYCLING OF BERYLLIUM
Beryllium is a naturally occurring element (atomic number 4) and is one of the lightest of elements with an atomic weight of 9.012. Beryllium enters the air, water and soil as a result of natural and human activities. Beryllium is ubiquitous in nature, typically occurring as a mineral silicate. It is the 44th most abundant element in the earth’s crust. Beryllium is typically found at levels of 0.5 to 2 ppm in soils and rocks throughout the world. Extracted pure beryllium (Be) is a hard grayish-white metal of the alkaline earth family. Beryllium does not occur naturally in its pure form. Because beryllium occurs in trace quantities in all soil and rock, as a result of weathering, it is released as a particulate compound to air, water and sediments.
The only minerals mined for purposes of extracting beryllium metal are bertrandite (0.5 – 1.0% Be) and beryl ores (0.5 – 3.5% Be). The gemstone Emerald is a beryl mineral.
Clay and mineral-based materials used to make products for use in manufacturing, construction and consumer products contain trace quantities of beryllium. These materials are not used because of the trace amounts of beryllium they contain. Common examples include oil-dry, oil, emery cloth, grinding wheels, coal, abrasive blast media, concrete, bricks, roofing shingles, kitty litter, charcoal, laundry detergent and ceiling tiles. These materials contain beryllium at concentrations typically found in soils.
The use of clay and mineral-based materials containing trace quantities of naturally occurring beryllium in manufacturing can result in worker exposures in excess of the EU 8-hour occupational exposure limit for beryllium in very dusty operations. It is important to understand that beryllium-related disease has not been found in studies of workers exposed to trace beryllium originating from natural materials or from processing materials where beryllium has not been intentionally added for its unique properties.
NATURAL BERYLLIUM IN THE ENVIRONMENT
Minerals containing beryllium occur naturally in ground and surface waters. Beryllium contained as mineral chemical compounds are largely water insoluble, have a low aqueous solubility, and are carried in suspension within the environment. Particles carried in suspension are much more influenced by turbulence and velocity effects. Such particles will be carried in suspension as long as the water velocity remains constant. In deeper areas, where the water pools, or areas along the outer edge where the water slows down, particle sedimentation or drop out usually begins. (Mason & Dragun 1996)
BERYLLIUM IN WATER
Beryllium is naturally emitted to the atmosphere by windblown dusts and volcanic particles. Mineral or soil particles that are sufficiently small may be picked up and carried aloft by surface and prevailing winds. While prevailing winds may carry extremely light particles high into the atmosphere, most particles are too large and too heavy to be carried into the upper atmosphere. Thus, airborne beryllium silicate particles will most likely settle onto adjacent land and water surfaces. (Mason & Dragun 1996) Human related sources of beryllium such as the combustion of coal and fuel oil contribute to airborne levels of beryllium. Particles produced from such human processes are generally much too large and too heavy to move into the upper atmosphere. (Toxicological Profile for Beryllium – 1991)
The U.S. Agency for Toxic Substances and Disease Registry (ATSDR) has estimated that within the United States, about 45% of airborne beryllium is due to human activity releases of particulate containing beryllium. Natural sources, such as windblown dust and volcanic activity, account for 55% of beryllium released to the atmosphere.
BERYLLIUM IN AIR
Since beryllium occurs naturally in all soils and sediments, it is commonly found in numerous plants and foodstuffs. The ATSDR reported a median concentration of beryllium in 38 foods at 22.5 μg/kg (PPB) fresh weight (excluding kidney beans) with a range of concentrations from <0.1–2,200 PPB. The highest concentrations were reported for kidney beans (2200 PPB), crisp bread (112 PPB), garden peas (109 PPB), parsley (77 PPB), and pears (65 PPB). The average concentration of beryllium in fruit and fruit juices is 13.0 μg/L (PPB) with concentrations ranging from not detected to 74.9 μg/L.
BERYLLIUM IN PLANTS & FOODSTUFFS
It is commonplace to detect natural beryllium on surfaces in public and private places, including workplaces that do not process materials where beryllium was intentionally added for its unique properties and characteristics.
NATURAL BERYLLIUM IN EVERYDAY LIFE
Natural beryllium can be found in materials and products commonly used or found in general manufacturing. Similar to what occurs in public settings, a significant source of beryllium commonly found in general manufacturing and even in office work environments is the result of normal drag-in of soil on shoes. In addition to the drag-in of soil, in general manufacturing settings where materials or products not containing intentionally added beryllium are processed or used, it is common to detect beryllium on surfaces. It is important to note that there are no health-based standards for beryllium-containing particulate present on surfaces, no matter whether the source is natural beryllium or intentionally added beryllium. Beryllium surface level guidance does exist for beryllium processing sites for the purpose of monitoring levels of cleanliness to support housekeeping efforts. These guidance levels are not derived by an association with a health risk.
BERYLLIUM IN NON-BERYLLIUM MANUFACTURING ENVIRONMENTS
According to the WHO Beryllium in Drinking Water Background document development of WHO Guidelines for Drinking Water Quality 2009, the general population may be exposed to trace amounts of beryllium by inhalation of air, consumption of drinking-water and food, and inadvertent ingestion of dust. The estimated total daily beryllium intake in the USA was 423 ng, with the largest contributions from food (120 ng/day, based on daily consumption of 1200 g of food containing a beryllium concentration of 0.1 ng/g fresh weight) and drinking-water (300 ng/day, based on daily intake of 1500 g of water containing beryllium at 0.2 ng/g), with smaller contributions from air (1.6 ng/day, based on daily inhalation of 20 m3 of air containing a beryllium concentration of 0.08 ng/m3) and dust (1.2 ng/day, based on daily intake of 0.02 g/day of dust containing beryllium at 60 ng/g).
1. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Beryllium. ATSDR. Atlanta (2002).
2. World Health Organization, Background Document for Development of WHO Guidelines for Drinking water quality (2009).
NATURALLY OCCURRING BERYLLIUM EXPOSURES
IN NON-OCCUPATIONALLY EXPOSED PERSONS
RECYCLING OF BERYLLIUM
Pure beryllium metal components used in technological applications have extremely long lifetimes, and therefore
return to the recycle stream very slowly. Some, because of applications in space, or because of their sensitive military
nature, do not return at all. When pure beryllium components do finally return, they can be easily recycled. In process
scrap, for example at machining operations is gathered and returned for recycling. In all cases, the recycling of
beryllium metal results in a significant energy saving of over 70% compared to extracting beryllium from ore.
Recovery of Be metal from beryllium-containing alloys in scrap (for example, the copper beryllium components
included in end of life electronics) is not performed because of the small size of the components and the very low
beryllium content per device (less than 40 ppm, even in devices with the highest beryllium content). Alloys containing
beryllium make up approximately 0.15% of all copper alloys used in electrical equipment, which during pre-processing
of end-of-life equipment are collected together with other copper in the scrap and subsequently diluted to ~ 2 ppm in
the copper recycling stream. In responsible copper recycling processes that currently exist in the EEA, the extremely
small quantities of beryllium metal are immobilized in slags, separated form the recycled copper and do not present an
exposure hazard to recovery workers or a hazard to the environment.
Results of a quantitative survey for exposure to airborne metals, including beryllium, conducted on workers shredding,
picking and separating significant volumes of WEEE in an EU recycling plant:
Eight work operations were selected for sampling.
Pre Sort, Q140 Shredder (Operator), Picking (Ferrous), Picking (Eddy current drops), Q100 Shredder (Operator), Water Tables (Operator), Cyclone (Operator), and Electrostatics.
For each operation 15 to 17 full shift personal air samples were collected over an 8-week sampling period. Each sample was analyzed to determine the total mass of 25 metals present including beryllium.
All airborne beryllium exposures were below 0.0002 milligram per cubic meter (mg/m3) and statistical analysis demonstrated that exposures to beryllium are anticipated to be below 0.0002 mg/m3 for greater than 95 percent of the time