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Funding Information: The work was funded by the National Institute of Allergy and Infectious Diseases, National Institutes of Health grants U19AI111276 and U01AI065663 to R.R.R., R.D., J.J.E. and P.S., and NIAID training grant T32AI125185 to A.L. The study sponsors were not involved in the study design, in the collection, analysis, and interpretation of data; in the writing of the manuscript; or in the decision to submit the manuscript for publication. Publisher Copyright: © 2022, The Author(s). Mechanisms underlying variability in transmission of Mycobacterium tuberculosis strains remain undefined. By characterizing high and low transmission strains of M.tuberculosis in mice, we show here that high transmission M.tuberculosis strain induce rapid IL-1R-dependent alveolar macrophage migration from the alveolar space into the interstitium and that this action is key to subsequent temporal events of early dissemination of bacteria to the lymph nodes, Th1 priming, granulomatous response and bacterial control. In contrast, IL-1R-dependent alveolar macrophage migration and early dissemination of bacteria to lymph nodes is significantly impeded in infection with low transmission M.tuberculosis strain; these events promote the development of Th17 immunity, fostering neutrophilic inflammation and increased bacterial replication. Our results suggest that by inducing granulomas with the potential to develop into cavitary lesions that aids bacterial escape into the airways, high transmission M.tuberculosis strain is poised for greater transmissibility. These findings implicate bacterial heterogeneity as an important modifier of TB disease manifestations and transmission. publishersversion published

An effective vaccine is needed for the prevention and elimination of malaria. The only immunogens that have been shown to have a protective efficacy of more than 90% against human malaria are Plasmodium falciparum (Pf) sporozoites (PfSPZ) manufactured in mosquitoes (mPfSPZ)

Perchlorate (ClO4 −) is an emerging contaminant whose presence and origin is of considerable environmental interest. This article discusses known sources of perchlorate and available forensic techniques to distinguish between naturally occurring and anthropogenic origins. Forensic techniques presented include stable isotopic analysis (37Cl/35Cl, 87Sr/86Sr, 16O/17O), surrogates analysis (nitrates, sodium, chlorides, phosphate, nitroglycerins, metals, strontium), historical information assessment (aerial photography, propellant use and chemistry, firing range usage), geologic analysis (limestone, caliche, playa crusts, hanksite [Na22K(SO4)9 (CO3)2Cl], potash, phosphate ore, etc.), x-ray diffraction (XRD), and scanning electron microscopy (SEM). In this article, the detection of a source of naturally occurring perchlorate in soil and groundwater associated with the Mission Valley Formation in San Diego California is presented. Modification of existing agricultural soil sampling techniques USDA 60-6(...

†Dr. Robert D. Morrison is a Soil Physicist with DPRA, Inc. He has a BS in Geology, a MS in Environmental Studies, a MS in Environmental Engineering and a Ph.D. in Soil Physics from the University of Wisconsin at Madison. Dr. Morrison has been working for 30 years in the environmental field on issues related to soil and groundwater contamination. Dr. Morrison specializes in the forensic review and interpretation of scientific data for the purpose of identifying the source and age of a contaminant release. Emily A.Vavricka is an Environmental Scientist with DPRA, Inc. She possesses a BS in Environmental Science from the University of California, Riverside, and specializes in the use of environmental forensics for use in litigation matters.

1,4-dioxane (dioxane) is an emerging contaminant of concern and is quickly gaining dominance as a key contaminant in groundwater. Domestic and municipal water-supply wells have been impacted by 1,4...

Dendroecology and phytoscreening investigations are emerging forensic techniques that have attained scientific maturity in terms of their ability to provide corroborative evidence of contaminant releases in soil and groundwater. In some cases, dendroecology can also provide insight regarding causal relationships between a contaminant release and the presence of the same contaminant in a tree ring. A recent evolution of dendroecology investigations is the development of solid-phase microextraction (SPME) sampling techniques, which allow continuous sampling and provide lower detection limits than traditional head-space analysis of tree core samples.

Chlorinated solvents, especially tetrachloroethene (perchloroethylene or PCE), trichloroethylene (TCE), and methyl chloroform (1,1,1-trichloroethane or TCA) are among the most widespread volatile organic compounds (VOCs) detected in soil and groundwater. Given their frequency of detection in environmental investigations, techniques to age date and identify the origin of chlorinated solvent releases are of great interest in environmental forensic investigations. Since the 2007 publication of the second edition of Introduction to Environmental Forensics, additional forensic techniques and/or refinements of existing methods specific to chlorinated solvents have arisen, including diagnostic stabilizers, manufacturing impurities, compound-specific isotope analysis (CSIA), and reconstructed plume techniques, which are the focus of this chapter.

In 2001 it was estimated that approximately 75% of all dry cleaning facilities in the United States (U.S.) were contaminated, primarily with perchloroethylene (PCE). In a 2002 survey of 26 dry cleaning sites in California, PCE was detected at 85% of the sites. In 2008, the U.S. EPA estimated that 15,750 active dry cleaners required remediation while a Florida study of 150 contaminated dry cleaner sites revealed that contaminated groundwater had migrated off-site at approximately 57% of the facilities. Regardless of the actual number of PCE contaminated dry cleaning facilities in the U.S., their investigation and remediation will require decades and consume billions of dollars. A challenge in the forensic investigation of dry cleaning facilities is the reconstruction of a PCE release after the facility has undergone remediation and/or no opportunity exists for sample collection. While standards for conducting traditional environmental investigations are available, an accepted forensic investigative methodology specific to dry cleaners is not. A methodical sequence of activities is needed for conducting an environmental forensic investigation of a dry cleaning establishment to insure that the ability to identify the source and age of a contaminant release is optimized.

Manufacturing impurities in chlorinated solvent products are of significant forensic importance for bracketing when a release occurred and/or identifying the source. While forensic techniques traditionally used for age dating and source discrimination, such as compound specific isotope analysis (CSIA), isotopic and chemical ratio analysis, reconstructed plume techniques, surrogate chemical indicators and stabilizers are available, less emphasis has been given to the use of manufacturing impurities as a corroborative technique. The use of manufacturing impurities in PCE (tetrachloroethylene) and TCE (trichloroethylene) produced via the oxychlorination of acetylene or ethylene offers a means to estimate when these chlorinated solvents were produced. Of the, the 1,1,2,2-tetrachloroethane (1,1,2,2-TeCA) is one of the various manufacturing impurities generated when producing TCE, PCE and methyl chloroform. TeCA provides the means to identify that the solvent was manufactured prior to about 1977. This chapter discusses the historical use, synthesis, physiochemical properties and applications of TeCA.

The source and timing of a release of contaminants from an underground storage tank (UST) and/or associated piping system is a common environmental forensic challenge. Assuming that the UST and piping has not been removed, high-density soil sampling and analysis can provide insight regarding the source of a release, although it rarely provides forensic information regarding when the release occurred. Absent direct evidence regarding when the release occurred and/or the availability of diagnostic chemical indicators, corrosion modeling can be used. Corrosion models presented in this chapter that are used for this purpose include the Rossum, PACE, MTCF, TSS, and MTFF for USTs and underground piping.

Absent direct observations or documentation, contaminant-specific transport models are often the only available means to reconstruct the origin and age of a contaminant release into the soil, soil vapor, or groundwater. Categories of forensic contaminant transport models examined in this chapter include liquid releases on a paved/unpaved surface, liquid and vapor transport in the unsaturated zone, and groundwater models. The proper application of these models and the means to couple them into a comprehensive approach to estimate when a contaminant entered groundwater and/or its relationship with a known contaminant plume are presented. An analysis of the use and limitations of groundwater inverse models is evaluated, especially in terms of uncertainties associated with the mass flux rate into the groundwater for the contaminant(s) of interest.

(2002). The Forensic Detection of Explosives in the Subsurface. Environmental Claims Journal: Vol. 14, No. 3, pp. 351-367.

(2002). Contaminant Source Identification with Soil Gas Surveys. Environmental Claims Journal: Vol. 14, No. 1, pp. 99-111.

A multitude of forensic techniques are available for age dating and source identification, including aerial photography interpretation, corrosion models, the commercial availability of a compound, chemical associations with discrete type processes, chemical profiling, degradation models and contaminant transport models. These techniques, however, are rarely challenged or discussed in the literature relative to the scrutiny encountered in environmental litigation. When introduced as scientific evidence, the governing assumptions and quality of the data are critically evaluated and frequently successfully challenged. The purpose of this paper is to review five types of forensic techniques and discuss their merits so that a user can decide which technique, or combination of techniques, is most appropriate for developing the technical portion of a case.

Historical aerial photography can be a powerful tool in environmental forensic investigations. Historical aerial photography is available for many sites from the 1930s on. It is researched and obtained from both public and private sources. Most of the photography consists of vertical stereoscopic film annotated with the date of the photomission. A current photomission can be flown using airborne GPS for precise registration of the photomosaics. The photography is scanned at a very high resolution and registered in a coordinate system using a digital stereoplotter that removes terrain distortion and allows the precise measurement of objects. The digital stereoplotter is used to produce photomosaics and to interpret environmentally significant features in the photography. The accuracy of the environmental interpretations is dependent on the skill and experience of the interpreter as well as the resolution of the photography and quality of the equipment used. The photomosaics are then registered in a geographic information system along with the interpretations of environmentally significant features. In a similar manner, historic maps are scanned and registered into the same coordinate system. The interpreted images and maps form a significant part of the expert report. A computer projection system is used to show the interpreted images at trial.

A multitude of forensic techniques are available for age dating and source identification, including corrosion models for underground storage tanks, the commercial availability of a compound, chemical associations with discrete types of manufacturing processes, chemical profiling, proprietary additives, stable isotope analysis, degradation models, biomarkers and contaminant transport models. The selection and use of these techniques in environmental litigation must be thoroughly understood and applied to be effective as forensic evidence. When introduced as scientific evidence, the governing assumptions and quality of the data are critically evaluated and frequently successfully challenged. The purpose of this paper is to present an overview of commonly used environmental forensic techniques and their possible applications so that a user can decide which technique or combination of methods is most appropriate for their case.

Laboratory and field research indicate that the surface release of pesticides, which are essentially insoluble in water, typically result in their strong retention in shallow soils with limited mobility to depth. In contrast, at a pesticide mixing facility in Fresno, California, hydrophobic pesticides (DDT and Toxaphene) were detected at depths exceeding 30 ft. The estimate time required for DDT and Toxaphene to migrate to a depth of 10 ft in aqueous solution due to rainfall infiltration was calculated to be 20,000 and 2000 years, respectively. Mechanisms capable of transporting these compounds therefore were examined, including colloidal transport, transport via preferential pathways, mechanical transport, and transportation by a solvent or solvent mixture. The presence of DDT at depth in some locations was due to the presence of dry wells, cisterns, or landfills. In areas where these features were not present, DDT and Toxaphene is believed to have been transported to depth via dissolution into a solvent...

In 1992 an obscure 23 page report titled Dry Cleaners – A Major Source of PCE in Ground Water was published. Flush water was sampled to indicate whether PCE (perchloroethylene) liquids or sludges had accumulated. Of the sixteen dry cleaners investigated, samples from 11 indicated that PCE sludges or liquids had accumulated in the sewers next to the facility and were available for exfiltration. Based on the investigation, the report stated: The literature indicates that all sewer lines leak to some extent. This led to the realization that the owners and operators of sewers, especially municipalities, were potentially liable for PCE releases via a sewer network. While the exfiltration of liquid from sewers is a mature science to engineers designing sanitary sewers, the application of this knowledge specifically to forensic issues associated with PCE releases from sewer piping is unique. This chapter provides insight into this issue, especially its application to forensic issues that arise in litigation regarding PCE discharges from sewers.

The transport time required for a contaminant to move through the subsurface is frequently encountered in insurance coverage cases. Transport calculations are often offered as evidence that (1) a contaminant was released within a particular policy period or (2) a contaminant entered the soil and/or groundwater during a specific policy period. The various transport processes and the assumptions used in these calculations are presented along with examples in this article.

The Pherocon Ic trap captured the greatest number of Cydia caryana (Fitch) adult males and all trap designs appeared to represent population trends equally well. Pooled data from all trap height experiments indicate that traps placed 9.14 m above the orchard floor captured significantly more adult males than those placed at 4.57 m height. Horizontal placement of traps within the tree canopy indicated a significantly greater capture in the central portion of the canopy than at other locations. Correlations between the total capture of male adults and the rate of fruit infestation were not significant.

Emergence of hickory shuckworm, Cydia caryana (Fitch), adults from larval overwintering sites was bimodal. The major emergence peak occurred during the period of mid-March to mid-May and the smaller activity period during July and August. Pheromone trapping was effective for monitoring population trends during generations 1 and 5 of C. caryana but less so during generations 2, 3, and 4. Activity patterns suggest the species is crepuscular rather than truly nocturnal.