Methods of passively sampling PFAS in the environment, PFAS sorbents, apparatus and systems (apparatus plus conditions) for sampling groundwater, porewater, and surface water are described.

A process for detecting oil or lubricant contamination in the production of an article by adding a Stokes-shifting taggant to an oil or lubricant of a machine utilized to produce the article or a component thereof, irradiating the articles produced with a first wavelength of radiation, and monitoring the articles for emission of radiation at a second wavelength. The taggant can be in the form of a composition containing a Stokes-shifting taggant, which absorbs radiation at a first wavelength and emits radiation at a second wavelength, different from said first wavelength, dissolved or dispersed in an oil or lubricant.

A method for the detection of hydrocarbon contamination in a sample is disclosed. The method includes contacting a sample with a molecular probe. The molecular probe has a photoluminescence which is environmentally sensitive. The photoluminescence from the molecular probe is collected. The method includes determining whether the photoluminescence is indicative of a hydrocarbon contaminated sample. A test strip for the detection of hydrocarbon contamination in a sample is also disclosed. The test strip includes a molecular probe embedded in a substrate and/or immobilized to the substrate, the molecular probe having a photoluminescence which is environmentally sensitive to hydrocarbon contaminated sample.

An embodiment provides a method for deriving an amount of PFAS substances from a total organic fluoride measurement in a sample, including: removing inorganic fluoride from the sample using one or more of an ion exchange cartridge and an exclusion apparatus; preconcentrating, using a solid phase extraction, at least one PFAS substance in the sample; digesting, using a working electrode and a counter electrode, the at least one PFAS substance to an amount of total organic fluoride; and determining, using an analyzer, the amount of total organic fluoride in the sample. Other aspects are described and claimed.

A method for identifying and analyzing dissolved organic nitrogen of different sources in wastewater includes extracting DON in wastewater to obtain a DON extract, detecting mass spectrum peaks in the DON extract, pre-processing the spectral data of the wastewater sample; constructing a network relationship of the substance reaction in the wastewater sample; screening the substance reaction relationship of DON; and determining different sources of DON.

A passive sampling device is provided that is comprised of a member having a first surface and a second surface opposite the first surface and a hole through the member extending from the first surface to the second surface. An adsorbent material is positioned between two mesh members. The adsorbent material allows for efficient and selective removal of organic molecules, such as, for example, perfluoroalkyl substances.

A reagent dispenser includes a housing. A container of microbial inhibitor is disposed within the housing. A dispensing system is disposed within the housing and operable to dispense the microbial inhibitor from the container. The dispensing system is calibrated to dispense a calibrated weight per water sample of the microbial inhibitor, such that a ratio of the calibrated weight per water sample to inner volume of a sample bottle substantially equals a predetermined concentration of microbial inhibitor per liter of water determined to acidify water to a pH of 4 or less.

The measurement of glutaraldehyde-based biocides in seawater without the use of a derivatization agent. The measurement of glutaraldehyde-based biocides in seawater may be performed without additional components to reduce background interferences. The concentration of a glutaraldehyde-based biocides in a seawater sample is determined using reversed phase liquid chromatography and a gradient mobile phase of acetonitrile and deionized water. Systems for determining the concentration of glutaraldehyde-based biocide in a seawater injection system are also provided.

Described herein are systems, methods, and devices for detecting harmful algae blooms. An example system includes autonomous watercraft; and a computing device operably connected to the autonomous watercraft over a network, the computing device including a processor and a memory having computer-executable instructions stored thereon that cause the processor to: surveil a body of water for an algae growth; receive a local condition at the body of water; predict a spread of the algae growth in the body of water based on the local condition; determine a deployment strategy for the autonomous watercraft based on the spread of the algae growth; and transmit one or more control signals to the plurality of autonomous watercraft based on the deployment strategy, where the autonomous watercraft are configured to collect and analyze a plurality of water samples to determine whether the algae growth is a harmful algae bloom.

A biological toxicity test method for evaluating an ecological safety of an advanced oxidation process comprising the following steps: (1) collecting (preparing) a waste water to be determined; (2) collecting the waste water and a tap water after the advanced oxidation process treatment; (3) subjecting Koi (Cyprinus carpio haematopterus) to the water after treatment for exposure to poison; (4) Determining an anti-oxidation enzyme activity of a liver of the Koi after exposure; (5) Data analyzing. By comparing the changes of liver enzyme activities in different water, the present method evaluates the toxicity changes of micro-pollutant containing water before and after treatment, which fills in the gap of the ecological risk assessment for advanced oxidation technology.