Biomedical Engineering Reference
In-Depth Information
irradiation, can ensure complete destruction of all temperature-resistant
contaminants. One potential drawback of autoclaving is the possible pro-
duction of leachable by-products from the plastics or biopharmaceutical
components, which can also result from predecontamination with chlorine
dioxide, leading to a higher risk of soil and water contamination through
landfill leakage. The use of chlorine as a disinfectant is not regarded as
environmentally sound because it can lead to undesirable atmospheric
emissions. Wastes that are strongly acidic or caustic through contamina-
tion with pH control or CIP agents must be neutralized before landfilling.
Untreated, and ground and autoclaved (or otherwise decontaminated)
waste exhibits high long-term stability in landfills and is not susceptible to
biodegradation. As a consequence, no methane is produced in this fraction
of landfilled waste. As energy is required for waste pretreatment and trans-
port, the overall energy balance for waste disposed in a landfill is negative.
Landfill
Some companies choose landfilling. Its potential as an option varies
based on municipal and regional regulations as well as on a product's use
before disposal.
Untreated: One industry player landfills an untreated component
because its system does not require prior treatment. Another com-
pany whose products do not require landfill pretreatment uses bio-
hazard bags before disposal in solid waste trash.
Treatment
Depending on the application, some companies decontaminate with a dose
of chlorine dioxide or other deactivator and then dispose of the item in a
landfill. This option is more expensive than disposing of an untreated com-
ponent because it requires extra steps before landfilling. It does, however,
allow for the product to be landfilled after use without other cleaning and
decontamination steps.
All materials used in the manufacture of disposables contain extractables
and leachables. In landfills, where both aerobic (oxidative) and anaerobic
(reductive) conditions occur, both of these types of products will be found
in the vicinity of deposited waste material. Leachables, by their definition,
will be released from plastics under normal landfill conditions. These may
