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Maintaining kiwifruit firmness is key to global supply chain. Controlled atmosphere (CA) technology can maintain kiwifruit quality. However, there is a risk of ethylene (C2H4) accumulation in CA that may accelerate kiwifruit softening. The objectives of this study were to determine the impact of ethylene on kiwifruit quality in CA. 'Hayward' kiwifruit were stored in air and CA (5% CO2 + 2% O2) at 0°C, 95% RH for 13 weeks. Ethylene at concentrations of 10, 100, 1000 nL·L−1 was added after 3 weeks of storage. The responses of kiwifruit to ethylene were dose-dependent in both air and CA storage. Ethylene-induced kiwifruit softening was delayed and slowed by CA. However, white-core inclusions (WCI) disorder was observed after 8 weeks of exposure to 100 and 1000 nL·L−1 ethylene in CA. The lowest concentrations of ethylene (≤ 10 nL·L−1) in CA did not influence kiwifruit quality. This work demonstrates that kiwifruit sensitivity to ethylene is lower in CA than that in air, but excessive softening and WCI may negatively impact kiwifruit quality when exposed to a high ethylene concentration in CA for extended periods. Hence, ethylene monitoring and management may be less critical in kiwifruit stored in CA but are required. [ABSTRACT FROM AUTHOR]

During kiwifruit storage, quality monitoring is required for inventory planning and consistent quality maintenance. Commercial near-infrared (NIR) spectrophotometers showed reduced performance in the estimation of kiwifruit flesh firmness (FF) as the FF estimation is indirect and can be affected when both, textural structures and absorbing compounds, change during postharvest ripening. Laser backscattering imaging (LBI) records the backscattered signal after a single laser beam interacts with kiwifruit tissue, including merged information on light absorption and scattering. Measurements were carried out at 830 nm, where scattering is most dominant. In this work, time series of kiwifruit 'Zesy002' (n = 30) and 'Hayward' (n = 30) LBI were collected through the postharvest ripening during a 15-day shelf life at 20°C. Four LBI parameters capturing DIP, FWHM, SLP and HWQM were selected in this study. "Zesy002' DIP, FWHM, SLP, and HWQM increased approx. 0.6 cm, 0.2 cm, 0.3 and 0.14 cm, respectively. 'Hayward' LBI increased approx. 0.2 cm, 0.1 cm, 0.2 and 0.04 cm, respectively. Different initial LBI values between cultivars and LBI changes may reflect the actual stage of softening, affected by kiwifruit ripeness. In conclusion, time series analysis could be useful in describing kiwifruit LBI change during ripening and making forecasts. [ABSTRACT FROM AUTHOR]

Kiwifruit (Actinidia chinensis var. chinensis) firmness is routinely measured in a destructive manner for decision-making purposes. Thus, a population's quality is inferred by measuring a sample from that population. Consequently, studies have investigated non-destructive techniques for measuring fruit firmness. However, most of these studies have been restricted to a single season or focused on performance over long-term storage. This work compared non-destructive compression (1 mm deformation) and acoustic stiffness with flesh firmness measured with a penetrometer across three seasons. 'SunGold' kiwifruit were harvested from 11, 9 and 3 orchards on multiple occasions in 2020, 2021 and 2022, respectively. Kiwifruit was freighted to Palmerston North and assessed on arrival. Thirty fruit per orchard were measured on lab arrival, whilst 24 fruit per orchard were stored for two weeks at 0°C prior to assessment. The non-destructive methods had a strong (r2 > 0.89–0.92) segmented correlation with flesh firmness (0.52–10 kgf). Flesh firmness could be adequately estimated with the non-destructive methods within a season. However, segmented regression performance was reduced when predicting for a season outside of the training population. Nonetheless, these non-destructive methods may be useful for estimating flesh firmness at harvest and after short-term storage (2 weeks at 0 °C). [ABSTRACT FROM AUTHOR]

Perfluorononanoic acid (PFNA) is a commercially relevant, long-chain (8 fully fluorinated carbon) perfluorinated carboxylic acid. PFNA has limited terrestrial ecotoxicity data and is detected in humans, animals, and the environment. This study is the fourth in a series with the objective of investigating the toxicity of a suite of per- and polyfluoroalkyl substances (PFAS) detected on military installations in a mammal indigenous to North America. Peromyscus leucopus (white-footed mice, ∼25/sex/dose) were exposed via oral gavage to either 0, 0.03, 0.14, 1, or 3 mg PFNA/kg-d for 112 consecutive days (4 wk premating exposure followed by an additional 12 wk of exposure after onset of mating). Parental generation animals were assessed for potential reproductive and developmental effects, organ weight changes, thyroid modulation, and immunotoxicity. Pup weight and survival were assessed at postnatal days 0, 1, 4, 7, and 10. Change in liver weight was determined to yield the most sensitive dose response according to benchmark dose analysis, and serves as the most protective point of departure (BMDL = 0.37 mg/kg-d PFNA). Other effects of PFNA exposure included reduced formation of plaque-forming cells, which are indicative of functional immune deficits (BMDL = 2.31 mg/kg-d); decreased serum thyroxine (BMDL = 0.93 mg/kg-d) without changes in some other hormones; and increased stillbirths (BMDL = 0.61 mg/kg-d PFNA). Pup weight and survival were not affected by PFNA exposure. Combined with data from previous studies, data from Peromyscus provide a One Health perspective on health effects of PFAS. [ABSTRACT FROM AUTHOR]

The comparative toxicity of six per‐ and polyfluoroalkyl substance (PFAS)–free and one PFAS‐containing aqueous film‐forming foam (AFFF) was evaluated in an outbred mouse species as well as several in vitro assays. The in vivo toxicological profile of PFAS‐free AFFFs in short‐term, high‐concentration exposures is different than that of a PFAS‐containing AFFF. The PFAS‐containing reference product induced increased liver weights, while the PFAS‐free AFFFs were linked to either decreased or unaffected relative liver weights. The in vitro toxicological profile across PFAS‐free AFFFs was uniform except in the Microtox® assay, where thresholds were variable and spanned several orders of magnitude. This direct comparison of products through short‐term toxicity tests and in vitro screenings represents early data to support evaluation of potential regrettable substitutions when selecting alternative PFAS‐free AFFFs. Further work in diverse taxa (e.g., aquatic organisms, terrestrial invertebrates, birds) and mammalian studies capturing sensitive life stages will refine and expand this data set across a range of risk‐relevant toxicological endpoints. Environ Toxicol Chem 2023;42:2364–2374. Published 2023. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

There is an urgent need to understand the toxicity hazards of aqueous film forming foam (AFFF) replacement products to ensure the balance between performance and toxicity hazards and avoid regrettable substitutions during the rapid phasing out of per‐ and polyfluoroalkyl substance (PFAS)‐containing AFFFs. To address this need, we assessed the toxicity of six candidate PFAS‐free products via literature review, estimation techniques, and incorporation of testing data from whole products and compared them against one PFAS‐containing product. Then, we combined the relative hazards across human occupational exposure (e.g., concentrate, foam, or dilute exposures), human environmental exposure (e.g., training, emergency response, cleanup), and environmental exposure to aquatic, mammalian, and other terrestrial species using an index‐based scoring system to quantify potential hazards across these domains. We found that most PFAS‐free products in their concentrated form may cause dermal and ocular irritation, and aquatic toxicity may be a concern from direct or repeated environmental releases. Additionally, all PFAS‐free AFFF products assessed contain chemicals that are notable as plausible hazards resulting from release uncertainties (e.g., concentration, release volume, release timing), but the PFAS‐free AFFF products appear to have a lower likelihood of environmental persistence and bioaccumulation and to have lower oral human health toxicity than the PFAS‐containing reference product. Decision makers can use this information alongside cost–benefit, sustainability, or life‐cycle analyses to make a data‐driven decision for the adoption of PFAS‐free AFFF. Integr Environ Assess Manag 2023;19:1609–1618. © 2023 SETAC Key Points: Per‐ and polyfluoroalkyl substance (PFAS)‐free aqueous film forming foams (AFFFs) will present a toxicity profile different than current PFAS‐containing AFFFs.Most PFAS‐free products in their concentrated form may cause dermal and ocular irritation, and aquatic toxicity may be a concern from direct or repeated environmental releases.PFAS‐free AFFF products appear to have lower likelihood of environmental persistence and bioaccumulation and have lower oral human health toxicity than the PFAS‐containing reference product. [ABSTRACT FROM AUTHOR]

6:2 fluorotelomer sulfonate (6:2 FTS) has been used as a replacement for legacy per- and polyfluoroalkyl substances (PFAS). We assessed reproductive and developmental effects in a human-wildlife hybrid animal model based on the association of adverse effects linked to legacy PFAS with these sensitive life stages. In this study, white-footed mice were exposed orally to 0, 0.2, 1, 5, or 25 mg/kg-day 6:2 FTS for 112 days (4 weeks premating exposure plus at least 4 weeks mating exposure). Pregnancy and fertility indices were calculated, and litter production, total litter size, live litter size, stillbirths, litter loss, average pup weight, and pinna unfolding were assessed. Sex steroid and thyroid hormone serum levels were assessed. Body weight, histopathology, and immune function were also assessed in this study. Reproductive endpoints were not significantly altered in response to 6:2 FTS. Spleen weight increased in male mice dosed with 6:2 FTS. Immune function determined via a plaque-forming cell (PFC) assay was decreased in both male and female mice in the 2 highest doses. A low benchmark dose was calculated based on PFCs as the critical effect and was found to be 2.63 and 2.26 mg/kg-day 6:2 FTS in male and female mice, respectively. This study characterizes 6:2 FTS as being potentially immunotoxic with little evidence of effect on reproduction and development; furthermore, it models acceptable levels of exposure. These 2 pieces of information together will aid regulators in setting environmental exposure limits for this PFAS currently thought to be less toxic than other PFAS. [ABSTRACT FROM AUTHOR]

Modified atmosphere packaging (MAP) is a promising approach to extend the storage life of kiwifruit (Actinidia deliciosa) and reduce food waste at retail. To investigate the effect of MAP on maintaining fruit quality during post-storage shelf life, 'Hayward' kiwifruit were stored in MAP or air (perforated polyethylene film) at 1°C 60%–70% RH for 35 days before being repacked in either perforated film (air), a non-perforated (MAP) retail bag or in MAP with an ethylene scrubber (ES) and stored at 20°C 67%–70% RH for 10 days (simulating retail conditions). The atmospheres created by MAP were 12%–15% O2 + 3%–4% CO2 at 1°C and 12%–16% O2 + 7%–10% CO2 at 20°C. MAP reduced kiwifruit softening during coolstorage, and this benefit was maintained during subsequent shelf life. However, MAP in simulated retail conditions benefited only weight loss and SSC. Ethylene was detected only in retail bags with rotten fruit, including one with an ES, suggesting that an ES may not be sufficient to manage ethylene in retail conditions. The application of MAP in retail as a means of reducing fruit losses at the end of the supply chain requires further research attention. [ABSTRACT FROM AUTHOR]

Chloroacetanilide herbicides are used worldwide to control weeds that affect crops such as corn, soybeans, and cotton. These herbicides are frequently paired with a "safener," which prevents herbicidal damage to the crop without diminishing weed control. Formulated herbicide products that include safeners and other ingredients are infrequently assessed for toxicity. Our goal was to understand the potential toxicity of safeners and herbicide + safener formulations relative to the toxicity of associated active ingredients. We quantified the concentration of safeners in commercially available formulations and tested effects on nontarget algae, Raphidocelis subcapitata, when exposed to individual herbicide active ingredients, safeners, and commercial formulations. The median effective concentrations (EC50s) causing 50% reduction in population growth for the herbicide active ingredients S‐metolachlor and acetochlor were 0.046 and 0.003 ppm, respectively. The safeners benoxacor, AD‐67, furilazole, and dichlormid were all substantially less toxic than the herbicides and were not toxic at environmentally relevant concentrations. The commercial formulations Dual II Magnum®, Me‐Too‐Lachlor II®, Harness®, and Surpass EC® all resulted in EC50 values that fell within the 95% confidence interval of the associated active ingredient herbicide. Interestingly, a significant increase in cell size was observed when algae were exposed to all the formulations, herbicides (acetochlor and S‐metolachlor), and safener (dichlormid). The safener furilazole caused a significant decrease in cell size, whereas benoxacor and AD‐67 had no observed effect on algae cell size. Significant algae cell size effects all occurred at or above the EC50 concentrations for each chemical, suggesting that other morphological effects may be occurring. Importantly, safeners in commercial formulations appeared not to impact toxicity to R. subcapitata compared with the active ingredient alone. Environ Toxicol Chem 2022;41:1466–1476. © 2022 SETAC [ABSTRACT FROM AUTHOR]

Kiwifruit (Actinidia chinensis var. chinensis 'Zesy002') have a relatively long harvest season, where fruit will change in maturity and hence attributes. Harvest may be followed by a long postharvest storage period. Scuffing is the discolouration of kiwifruit skin in response to an injury. This injury is observed throughout the supply chain to some extent and thus, it is of interest to identify possible reasons that predispose kiwifruit to skin discolouration. In this work, maturity, as influenced by harvest date and estimated by firmness and total soluble solids, was investigated as a potential descriptor of scuffing susceptibility. 'Zesy002' kiwifruit were sampled from 11 orchards in New Zealand on three occasions (ISO weeks 12, 18 and 20) during the 2020 harvest season. Upon arrival to the lab, 24 fruit from each grower were non-destructively assessed prior to a deliberately controlled scuffing treatment and subsequently stored for 2 weeks at 0°C, to allow symptom development. Of the at-harvest maturity indicators, firmness was found to be the strongest indicator of scuffing susceptibility and severity of the damage. Further work is required to understand the physical or physiological reasons that cause softer fruit to be more susceptible to scuffing. [ABSTRACT FROM AUTHOR]

Kiwifruit is New Zealand's major contributor to fresh produce export, selling into nearly 60 countries globally. In developed countries dominated by modern retail, consistent cool chain practices throughout the supply chain enable high quality product delivery to end consumers. However, in other regions, traditional retail conditions (e.g. wet markets) contribute to significant fruit sales. The limited adoption or availability of refrigeration and the relatively high ambient temperature and humidity conditions pose a considerable challenge in maintaining product quality. To understand potential kiwifruit sales conditions in regions dominated by traditional retail pathways, a case study survey was conducted in India and Singapore. Environmental conditions (temperature, relative humidity and ethylene concentrations) and kiwifruit quality (firmness) were monitored at street vendor locations in India and at wet markets in Singapore. It was found that at the point of sale, temperatures frequently exceeded 30°C and ethylene concentrations were as high as 150 nL L−1. The major proportion of the fruit were at an edible firmness while a significant proportion of overripe fruit also existed. The observations from this case study indicate the necessity to understand kiwifruit physiological responses to these high shelf-life temperatures and ethylene concentrations that may occur under traditional market conditions. [ABSTRACT FROM AUTHOR]

Per‐ and polyfluoroalkyl substances (PFAS) are compounds manufactured for use in paints, cleaning agents, fire suppressants, nonstick cookware, food containers, and water‐resistant products. Concerns about PFAS stem from their ubiquitous presence in the environment, persistence, and variable/uncertain bioaccumulation and toxicity. In the present study, 5 perfluoroalkyl acids and one polyfluoroalkyl substance were administered to white‐footed mice (Peromyscus leucopus) to elucidate the kinetics of each chemical over 28 d of exposure. Perfluorooctanoate, perfluorohexane sulfonate (PFHxS), and perfluorobutane sulfonate were administered to male and female mice via drinking water. Perfluorooctane sulfonate, perfluorononanoate, 6:2 fluorotelomer sulfonate, and PFHxS were administered to male and female mice via oral gavage. Blood samples collected after 14 or 21 and 28 d of exposure were analyzed for individual PFAS concentrations via liquid chromatography‐tandem mass spectrometry. In general, a plateau in serum concentration in this toxicity test–relevant timeline depended on interactions between 1) the type of PFAS (i.e., perfluoroalkyl sulfonic acids [PFSAs] vs perfluoroalkyl carboxylic acids [PFCAs] vs polyfluorinated), 2) continuous versus bolus dosing, and 3) to a lesser extent, sex. Specifically, PFCAs were detected at higher concentration in females than males, whereas PFSAs were generally detected at similar levels across sex. An exception occurred when PFHxS yielded higher serum levels in males than females through bolus, but not continuous, dosing. Type of PFAS had the largest impact on serum concentrations, whereas sex had the lowest. As such, future work on the toxicokinetics of PFAS in common ecological receptors would be valuable to further explore these patterns. Environ Toxicol Chem 2021;40:2886–2898. © 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Per‐ and polyfluoroalkyl substances (PFAS) are a large class of persistent chemicals used for decades in industrial and commercial applications. A key challenge with regard to estimating potential risk to ecological (and human) receptors associated with PFAS exposure lies in the fact that there are many different PFAS compounds and several to many can co‐occur in any given environmental sample. We applied a data science approach to characterize and prioritize PFAS and PFAS mixtures from a large dataset of PFAS measurements in surface waters associated with US Air Force Installations with a history of the use of aqueous film‐forming foams (AFFFs). Several iterations of stakeholder feedback culminated in a few main points that advanced our understanding of a complex dataset and the larger ecotoxicological problem. First, perfluorooctane sulfonate (PFOS) was often a dominant PFAS in a given surface water sample, frequently followed by perfluorohexane sulfonate (PFHxS). Second, a 4‐chemical mixture generally accounted for >80% of the sum of all routinely reported PFAS in a sample, and the most representative 4‐chemical mixture was composed of PFOS, PFHxS, perfluorohexanoic acid (PFHxA), and perfluorooctanoic acid (PFOA). We suggest that these results demonstrate the utility of formalized data science analysis and assessment frameworks to address complex ecotoxicological problems. Specifically, our example dataset results can be used to provide perspective on toxicity testing, ecological risk assessments, and field studies of PFAS in and around AFFF‐impacted sites. Environ Toxicol Chem 2021;40:871–882. © 2020 SETAC [ABSTRACT FROM AUTHOR]

Olive (Olea europaea L.) growing has outstanding economic relevance in Spain, the main olive oil producer and exporter in the world. Fruit skin properties are very relevant for fruit and oil quality, water loss, and susceptibility to mechanical damage, rots, and infestations, but limited research focus has been placed on the cuticle of intact olive fruit. In this work, fruit samples from nine olive cultivars ("Arbequina," "Argudell," "Empeltre," "Farga," "Manzanilla," "Marfil," "Morrut," "Picual," and "Sevillenca") were harvested from an experimental orchard at three different ripening stages (green, turning, and ripe), and cuticular membranes were enzymatically isolated from fruit skin. The total contents of cuticular wax and cutin significantly differed among cultivars both in absolute and in relative terms. The wax to cutin ratio generally decreased along fruit maturation, with the exception of "Marfil" and "Picual." In contrast, increased water permeance values in ripe fruit were observed uniquely for "Argudell," "Morrut," and "Marfil" fruit. The toluidine blue test revealed surface discontinuities on green samples of "Argudell," "Empeltre," "Manzanilla," "Marfil," and "Sevillenca" fruit, but not on "Arbequina," "Farga," "Morrut," or "Picual." No apparent relationship was found between water permeability and total wax coverage or the results of the toluidine blue test. The composition of cuticular waxes and cutin monomers was analyzed in detail, and sections of fruit pericarp were stained in Sudan IV for microscopy observations. Skin surface topography was also studied by means of fringe projection, showing large differences in surface roughness among the cultivars, "Farga" and "Morrut" fruits displaying the most irregular surfaces. Cultivar-related differences in cuticle and surface features of fruit are presented and discussed. [ABSTRACT FROM AUTHOR]