Traditional photography is unimaginable without the use of chemical solutions. In a crowded world it is
important to keep hazardous chemicals separate from the environment. Therefore, during the last few years,
around the world environmental legislation as well as workplace health and safety regulations have become
more stringent.
Our improved understanding of the impact of individual chemicals on the environment has allowed ILFORD to
consistently make improvements to reduce the effects of our products and wastes. This has included the
replacement of the chemicals of most concern as well as a reduction in the volume produced by our processes.
ILFORD products are famous for the highest quality in all aspects, and this includes workplace and
environmental safety.
Photo processing chemistry has not only to be judged in terms of its effects on man through possible exposure
in the workplace (see Fact Sheet entitled How can photographic chemicals enter and affect your body), but also
in terms of its effects on the environment after leaving the laboratory as waste. The main influence in estimating
environmental effects depends upon the method of disposal. Waste chemistry entering a natural waterway can be
more harmful to the environment than a solution properly disposed of by a waste handling company.
Today responsible photo laboratory owners either treat their waste before disposal or have it hauled away
by a licensed waste disposal company. However, wash water from photo processors, which contains very small
amounts of photo chemicals carried over from the processing tanks, can usually be discharged to the sewer.
This must of course be checked with your local waste company.
All these chemicals entering the sewer have to be judged concerning their biodegradability (ease of being destroyed
or broken down in the environment) and toxicity (hazard posed to the environment). Fortunately, most photographic
chemicals are non-toxic or easily biodegradable and therefore pose no problem for the environment. Micro-organisms,
growing in waste water treatment facilities or in rivers and lakes easily take care of them. The critical question
to ask is: are there any toxic, non-degradable compounds in ILFORD processes which have the potential to pass via
wash water through the waste water treatment plant and to harm the living environment in rivers and lakes? Clearly
the answer to this question is no! But let's have a look at some of the current issues:
Silver is present in very small amounts in developer and bleach and in moderate quantities (3-8 g/l) in fixer. Therefore some silver gets into the waste from the wash after fixing. Silver from a photographic process leaves the system as a non-toxic complex of thiosulphate. The binding of silver to thiosulphate is extremely strong and prevents the release of free silver ions (a toxic form of silver). Silver thiosulphate is rapidly transformed in the water purification plant to non-toxic silver sulphide which will not change further and is insoluble and therefore precipitates as sludge.
Hydroquinone is the main active ingredient in black and white and silver dye bleach developer solutions. In very dilute solutions hydroquinone decomposes in minutes. In most cases hydroquinone levels are already below the detection limit at the entrance to the water purification plant. If not, they are easily handled by the plant. However, in the past some water treatment plants have considered hydroquinone as being comparable to phenols (slowly degradable chemicals, which have a similar chemical structure to hydroquinone). The main problem of phenols is their ability to react with chlorine and form hazardous non-degradable compounds. Hydroquinone does not react in this way and any restrictions by water treatment plants based on such comparisions are not justified.
Sulphuric acid is a component of ILFOCHROME bleach. Since it is an acid it is highly corrosive to metals.
Therefore processor tanks need to be protected against corrosion.
Sulphuric acid, carried over from the bleach into the following tank is immediately neutralised by other
chemicals present. As sulphate, the neutralisation product of sulphuric acid, it has no impact on the environment.
Rapid fixers contain ammonium thiosulphate which, as the name implies, is a source of ammonium. It is not toxic and easily biodegradable. Ammonium enters natural waterways by the ton from farming and domestic waste water, which accounts for over 80% of the nitrogen added to the environment. It functions as a fertiliser, leading to excess algae growth in lakes and rivers. This unwanted effect makes the control of ammonium an environmental concern. If wash water from your processor is delivered to a modern water treatment plant, your ammonium will be fully broken down to nitrate and then to nitrogen.
EDTA is widely used as a chemical (sequestering agent) that can bind to ions such as iron, calcium, etc. and render them inactive. EDTA is not biodegradable and is not removed from waste water by water treatment plants. EDTA has been successfully removed from ILFORD products.
Boric acid and its salt borate are used in some ILFORD film developers, Hypam fixer and in ILFORD's P 4 developer as a buffer. Boric acid or borate entering a river or a water purification plant partly precipitates as calcium borate. In nature, borates are found in many different minerals. However, it is known, that dissolved borates in high concentration show some toxicity on plants. The borate level in ILFORD working strength chemicals is extremely low and presents no environmental hazard.
The oxygen demand (COD, BOD) of an effluent characterises the chemistry content and its degradability. A high COD (chemical oxygen demand) or BOD (biological oxygen demand) value means a high concentration of chemicals. Used tank solutions contain a high concentration of biodegradable chemicals and therefore have high COD and BOD values. Because of a possible impact on the environment through removal of oxygen, they are not recommended for disposal directly to drains. Photographic wash water CODs are low enough to be safely handled by your water treatment plant.
In many areas photo labs need a permit to discharge to sewers. It is important that water treatment plants know what quantities of chemicals are present in waste and from what kind of users they have been produced. Applying for a permit to discharge helps the water treatment plant to run its process in optimal conditions.
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