As a result, the total quantities reported by that company will be lower following delisting of a chemical, simply because the delisted chemicals are not included, not because the company reduced the amount of chemicals used. Companies move from one town to another. This means that when looking at totals for a community, the quantity of toxics used can go up or down not because of toxics use reduction, but instead because companies have moved in or out of the community. Facility identification numbers change. Occasionally that number will change, for example when a facility changes ownership or changes the nature of its business.
Some companies claim reportable data as trade secret.
In this case, although they still have to report the information, it is not included in the data presented here. Companies are allowed to claim reportable data as trade secret in order to protect proprietary manufacturing processes. Individual companies change the chemicals used, use less than the reportable quantity of a reportable chemical, or stop using TURA reportable chemicals altogether. Because of these differences, it is not always possible to add the different quantities reported and come up with a meaningful picture of how toxics use in Massachusetts has changed since 1990. This is especially true when looking at toxics use on the level of an individual community or company.