The pre-industrial makeup of the Gowanus area would have been identified as a tidal estuary—birds, fish, footlong oysters. Since the mid-nineteenth century, these Gowanus industries have included various forms of petrochemical processing: coal pockets, asphalt, coal and coke tar, gas and oil companies, as well as machine shops and lumber yards, chemical and paint plants, tin goods and iron foundries and power plants. These products and also the material waste—coal tar, solvents, spilled oil accruing in the canal's sediment—were the outputs of the factories. If these industries were organisms, these products would be the metabolites of the neighborhood. Metabolites operate in a series of intertwined loops. At some point in its cycle, it is likely to have been processed by microorganisms: ingested, only to be transformed and then secreted, followed by ingestion by yet another organism. The process of life as continual modification: ingestion, transformation, secretion, repeat is referred to in scientific terms as a metabolic pathway.