Per- and Polyfluorinated Substances, 'forever chemicals' (or maybe not)

Danas se u životnoj sredini mogu pronaći brojna hemijska jedinjenja koja je stvorio čovek u svojim laboratorijama. Ideja vodilja sredinom dvadesetog veka je bila kreirati jedinjenja kvalitetnih osobina koja će dugo imati upotrebnu vrednost a samim tim i dugo trajati. Neka od tih jedinjenja su danas prepoznata i kao „večne hemikalije”. Per- i polifluorovana jedinjenja (PFAS) su grupa sintetičkih hemijskih jedinjenja koja poseduju C- F, najjaču kovalentnu vezu. Zbog hemijske strukture koja im omogućava stabilnost na povišenim temperaturama, otpornost na niske pH vrednosti kao i visoku površinsku aktivnost, ova jedinjenja su u vidu različitih formulacija već nekoliko decenija našla široku primenu u brojnim potrošačkim proizvodima. Međutim, PFAS su poslednje dve decenije otkriveni u vodi, zemljištu, sedimentu, vazduhu, hrani i uzorcima biote na svim kontinentima, što prepoznato kao rizik za životnu sredinu i zdravlje ljudi. Zbog ovoga su u poslednjoj deceniji intenzivno testirane postojeće tehnologije za sanaciju i remedijaciju poput adsorpcije, filtracije, termalne destrukcije, oksidacije/redukcije kao i pranje zemljišta. Ipak, opisani su i brojni nedostaci ovih tehnologija

Global intercomparison of polyurethane foam passive air samplers evaluating sources of variability in SVOC measurements

Polyurethane foam passive air samplers (PUF-PAS) are the most common type of passive air sampler used for a range of semi-volatile organic compounds (SVOCs), including regulated persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), and emerging contaminants (e.g., novel flame retardants, phthalates, current-use pesticides). Data from PUF-PAS are key indicators of effectiveness of global regulatory actions on SVOCs, such as the Global Monitoring Plan of the Stockholm Convention on Persistent Organic Pollutants. While most PUF-PAS use similar double-dome metal shielding, there is no standardized dome size, shape, or deployment configuration, with many different PUF-PAS designs used in regional and global monitoring. Yet, no information is available on the comparability of data from studies using different PUF-PAS designs. We brought together 12 types of PUF-PAS used by different research groups around the world and deployed them in a multi-part intercomparison to evaluate the vari-ability in reported concentrations introduced by different elements of PAS monitoring. PUF-PAS were deployed for 3 months in outdoor air in Kjeller, Norway in 2015-2016 in three phases to capture (1) the influence of sampler design on data comparability, (2) the influence of analytical variability when samplers are analyzed at different laboratories, and (3) the overall variability in global monitoring data introduced by differences in sampler configurations and analytical methods. Results indicate that while differences in sampler design (in particular, the spacing between the upper and lower sampler bowls) account for up to 50 % differences in masses collected by samplers, the variability introduced by analysis in different laboratories far exceeds this amount, resulting in differences spanning orders of magnitude for POPs and PAHs. The high level of variability due to analysis in different laboratories indicates that current SVOC air sampling data (i.e., not just for PUF-PAS but likely also for active air sampling) are not directly comparable between laboratories/monitoring programs. To support on-going efforts to mobilize more SVOC data to contribute to effectiveness evaluation, intercalibration exercises to account for uncertainties in air sampling, repeated at regular intervals, must be established to ensure analytical comparability and avoid biases in global-scale assessments of SVOCs in air caused by differences in laboratory performance

Per- and Polyfluoroalkyl Substances - From Challenges To Potential Solutions

Per- and polyfluoroalkyl substances (PFAS) have emerged as significant environmental pollutants with far-reaching implications for both the environment and public health. These synthetic chemicals have been in use since the 1940s, finding applications in both industry and consumer products. Consequently, they have become pervasive in the environment, contaminating water sources, soil, and even the human body

Per- and Polyfluoroalkyl Substances - From Challenges To Potential Solutions

Per- and polyfluoroalkyl substances (PFAS) have emerged as significant environmental pollutants with far-reaching implications for both the environment and public health. These synthetic chemicals have been in use since the 1940s, finding applications in both industry and consumer products. Consequently, they have become pervasive in the environment, contaminating water sources, soil, and even the human body

Bioremediation of soils contaminated with PFAS: challenges, successes and future directions

Per- and polyfluoroalkyl substances (PFAS) are a class of anthropogenic organofluoride chemicals, widespread in industrial and consumer applications, well known for their unique and advantageous properties, such as their surface activity, thermal and chemical stability. However, the combination of their extensive use, bioaccumulative nature and adverse effects to the environment and human health has put them in the focus of scientific research as well as regulators with the aim to develop suitable remediation measures for polluted locations.PFAS resistance to degradation is attributed to the C-F bond. Despite being commonly cited as the strongest bond, the strength of C-F bonds in PFAS molecules varies significantly. PFAS structures, analyzed using density functional theory, reveal higher bond dissociation energies for primary C-F bonds than secondary ones, with longer fluoroalkyl chains exhibiting lower dissociation energies.This work aims to provide an overview on the current state of art of the most effective PFAS soil bioremediation strategies employed until now

Bioremediation of soils contaminated with PFAS: challenges, successes and future directions

Per- and polyfluoroalkyl substances (PFAS) are a class of anthropogenic organofluoride chemicals, widespread in industrial and consumer applications, well known for their unique and advantageous properties, such as their surface activity, thermal and chemical stability. However, the combination of their extensive use, bioaccumulative nature and adverse effects to the environment and human health has put them in the focus of scientific research as well as regulators with the aim to develop suitable remediation measures for polluted locations. PFAS resistance to degradation is attributed to the C-F bond. Despite being commonly cited as the strongest bond, the strength of C-F bonds in PFAS molecules varies significantly. PFAS structures, analyzed using density functional theory, reveal higher bond dissociation energies for primary C-F bonds than secondary ones, with longer fluoroalkyl chains exhibiting lower dissociation energies. This work aims to provide an overview on the current state of art of the most effective PFAS soil bioremediation strategies employed until now

The Pelagos Sanctuary for Mediterranean marine mammals: Marine Protected Area (MPA) or marine polluted area? The case study of the striped dolphin (Stenella coeruleoalba)

The concurrence of man-made pressures on cetaceans in the Mediterranean Sea is potentially affecting population stability and marine biodiversity. This needs to be proven for the only pelagic marine protected area in the Mediterranean Sea: the Pelagos Sanctuary for Mediterranean Marine Mammals. Here we applied a multidisciplinary tool, using diagnostic markers elaborated in a statistical model to rank toxicological stress in Mediterranean cetaceans. As a case study we analyzed persistent, bioaccumulative and toxic chemicals combined with a wide range of diagnostic markers of exposure to anthropogenic contaminants and genetic variation as marker of genetic erosion in striped dolphin (Stenella coeruleoalba) skin biopsies. Finally, a statistical model was applied to obtain a complete toxicological profile of the striped dolphin in the Pelagos Sanctuary and other Mediterranean areas (Ionian Sea and Strait of Gibraltar). Here we provide the first complete evidence of the toxicological stress in cetaceans living in Pelagos Sanctuary