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Links: Silvergrain Research User Information Testimonials & Feedback Click here to purchase Silvergrain Products Almost every photographic chemical which as ever been produced commercially includes compounds which are known to be hazardous to human health and/or the environment. Film and print developers are typically classed as MQ or PQ types, referring to combinations of Metol/Hydroquinone or Phenidone/Hydroquinone. Other developing agents such as Pyrocatechin, Pyrogallol, Amidol, Aminophenol, Glycin etc, are less commonly used, and have even higher levels of toxicity. Hydroquinone is perhaps the worst of the commonly used developing agents in terms of its potentially harmful effects, but nevertheless remains present in virtually all developers. Commercial photographic fixers commonly contain borates and other compounds which are known to have adverse environmental effects. Silvergrain products are completely free of the following chemicals:
During the 1980's and early 1990's the large photographic manufacturers conducted research into developing new darkroom chemicals based around isoascorbic acid (vitamin C). Ascorbic acid had been known as a safe developing agent for many years, but difficulties in designing effective photochemicals which used isoascorbic compounds resulted in only a few products ever reaching the market, and these continued to use hydroquinone in the solution. The most common developing agent, Metol, is a known toxic skin allergen and has a relatively short shelf life. In the latter part of the 20th century, new formulas replaced Metol with Phenidone compounds. Phenidone has a much longer shelf life and is virtually non-allergenic, but chemists continued to rely on Hydroquinone as the second developing agent, which is needed to produce effective contrast. With the advent of digital photography, the large manufacturers discontinued funding research into isoascorbic compounds and never fully resolved problems of stability. Independent researchers in the photographic community continued to experiment with non-traditional developing agents. One of the most prominent photo chemists whose specific research is based on stabilizing and improving ascorbate developers is Ryuji Suzuki. Knowing that ascorbic acid not only improved the health and environmental impact of photo chemistry, but that it was also capable of producing finer grain than either metol or hydroquinone, Suzuki begain experimenting with different compounds and made a complete study of all literature in the field. As a result, and after years of testing earlier versions, he produced formulas for DS-10, DS-12 and DS-14 which are available for free use on the Silvergrain.org web site. After gaining considerable use and recognition for these formulas Suzuki began to work with Digitaltruth Photo Ltd in 2005 to begin the manufacturing of a newer generation of products based on the existing published formulas. The new Silvergrain products, currently two print developers (Tektol Standard and Tektol Neutral), an alkaline fixer (Clearfix Alkaline Fixer), and a washing aid (Clearwash), are improved versions of the raw formulae and are manufactured in easy-to-use liquid concentrate form, allowing for full control of pH and water purity. Film developers and other photo chemical products are currently being developed for release in 2006/7. The Silvergrain line of chemicals is the most eco-friendly and least toxic darkroom chemistry on the market today. Silvergrain chemicals are designed to produce truly outstanding results and to have a shelf-life which exceeds that of most other products. Below is a list of compounds found in most photographic chemicals, with information on their health and environmental impact. These compounds are NOT used in Silvergrain chemistry: Hydroquinone: IARC: Group 3, not classifiable as to its carcinogenicity to humans. Confirmed animal carcinogen, very toxic to aquatic organisms. SYMPTOM(s): Eye irritation, conjunctivitis; keratitis; excitement; colored urine; nausea; dizziness; suffocation, rapid breathing; muscle twitches, delirium; collapse HEALTH EFFECTS: Cumulative Corneal damage (HE3); Mutagen (HE2) CNS effects (HE7); Suspect Teratogen (HE5)
US Dept. of Labor Occupational Safety & Health Administration International Labour Organization Occupational Safety & Health Information Centre Metol: Metol is a well-known skin allergen and many darkroom users have reported cases of skin reactions. Source of metol poisoning. According to The Film Developing Cookbook: "Metol has been known to cause an acute skin irritation known as metol poisoning. Metol poisoning often manifests itself only after years of exposure. Once the skin has become sensitized it usually remains so. Avoid direct contact." Irritating to the skin, eyes and respiratory tract. Repeated or prolonged contact may cause skin sensitization. The substance may have effects on the blood, resulting in lesions of blood cells. Very toxic to aquatic organisms.
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Borates (Boric Acid, Borax, Sodium Metaborate): Borates are commonly used in household and other products and are considered relatively safe for human exposure in small quantities; however, these compounds are also used in pesticides and known to cause environmental damage when used in high concentrations. Irritates the eyes, the skin and the respiratory tract - may cause effects on the gastrointestinal tract, liver and kidneys. Repeated or prolonged contact with skin may cause dermatitis. Animal tests show that this substance possibly causes toxic effects upon human reproduction.
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EDTA: A commonly used chelating agent, while current research shows little negative effect of EDTA exposure to humans in normal concentrations, it is potentially harmful to the environment. Salts of EDTA do not pass tests as "readily biodegradable," and will biodegrade very slowly under ambient environmental conditions.
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