Operational Considerations for Crew Fatality on the International Space Station.

BACKGROUND: While catastrophic spaceflight events resulting in crew loss have occurred, human spaceflight has never suffered an on-orbit fatality with survival of other crewmembers on board. Historical plans for management of an on-orbit fatality have included some consideration for forensic documentation and sample collection, human remains containment, and disposition of remains; however, such plans have not included granular detailing of crew or ground controller actions. The NASA Johnson Space Center Contingency Medical Operations Group, under authority from the Space and Occupational Medicine Branch, the Space Medicine Operations Division, and the Human Health and Performance Directorate, undertook the development of a comprehensive plan, including an integrated Mission Control Center response for flight control teams and Flight Surgeons for a single on-orbit crew fatality on the International Space Station (ISS) and subsequent events. Here we detail the operational considerations for a crew fatality should it occur during spaceflight onboard the ISS, including forensic and timeline constraints, behavioral health factors, and considerations for final disposition of decedent remains. Future considerations for differential survival and crewmember fatality outside of low-Earth orbit operations will additionally be discussed, including consideration of factors unique to planetary and surface operations and disposition limitations in exploration spaceflight. While the efforts detailed herein were developed within the constraints of the ISS concept of operations, future platforms may benefit from the procedural validation and product verifications steps described. Ultimately, any response to spaceflight fatality must preserve the goal of handling decedent remains and disposition with dignity, honor, and respect.Stepaniak PC, Blue RS, Gilmore S, Beven GE, Chough NG, Tsung A, McMonigal KA, Mazuchowski EL II, Bytheway JA, Lindgren KN, Barratt MR. Operational considerations for crew fatality on the International Space Station. Aerosp Med Hum Perform. 2023; 94(9):705-714.

Remains Containment Considerations for Death in Low-Earth Orbit.

BACKGROUND: Maintenance and disposition of decedent remains during spaceflight require the isolation of biohazardous products of decomposition in microgravity and in the absence of refrigeration. Containment and isolation options would preferably offer sufficient time to enable crew and ground support teams to determine appropriate disposition of remains and even potentially return remains to the Earth. The pilot study described herein undertook an effort to develop a postmortem containment unit for the isolation and maintenance of decedent remains in a microgravity environment.METHODS: Commercial off-the-shelf containment units were modified to meet the needs of a microgravity spaceflight environment and to offer the best likelihood of successful containment and management of remains. A subsequent evaluation of modified containment unit performance was undertaken utilizing human cadavers, with measurement and analysis of volatile off-gassing over time followed by impact testing of the units containing cadaverous remains in a simulated spaceflight vehicle seat.RESULTS: Modifications were implemented without significant negative design impact. Failure was observed in one modified unit after 9 d and attributed to improper filter application. The remaining unit successfully contained remains beyond the intended endpoint of the study.DISCUSSION: These pilot efforts offer important insight into the development of effective postmortem containment options for future spaceflight. Further study is needed to ensure repeatability of the findings and to further characterize the failure modes of the modified units evaluated, the impact of microgravity conditions, and the identification of additional modifications that would improve remains disposition.Houser T, Lindgren KN, Mazuchowski EL II, Barratt MR, Haines DC, Jayakody M, Blue RS, Bytheway JA, Stepaniak PC. Remains containment considerations for death in low-Earth orbit. Aerosp Med Hum Perform. 2023; 94(5):368-376.

Estimating postmortem interval for human cadavers in a sub-tropical climate using UV-Vis-near-infrared Spectroscopy.

Estimating postmortem interval (PMI) of surface found skeletal remains is challenging. This novel study used UV-Vis-NIR spectroscopy to scan soil collected from cadaver decomposition islands (CDIs) ranging from 15- to 963-d postmortem and control soils. A decomposition product spectra model (DPS model) was constructed by deducting the control soil spectra from the CDI soil spectra for the estimation of postmortem indices: PMI (d), ADD4 , ADD10 , and ADD20 . The DPS model (n = 55) was calibrated and subjected to a full cross-validation. Calibration R2 and RPD for the DPS model ranged from 0.97 to 0.99 and from 6.1 to 9.9, respectively, for the four postmortem interval indices. Validation R2 and RPD for the DPS model ranged from 0.73 to 0.80 and from 1.9 to 2.2, respectively. The DPS model estimated postmortem intervals for three test CDIs in a clay soil under perennial grassland (test set 1; n = 3) and six CDIs in a sandy soil under a loblolly pine forest (test set 2; n = 6). Test set 1 had PMI prediction ranges from -69 to -117 days, -796 to +832 ADD4 , +552 to +2672 ADD10 , and -478 to -20 ADD20 of observed PMI. Test set 2 PMI prediction ranged from -198 to -65 days, -9923 to +2629 ADD4 , -6724 to +1321 ADD10 , and -2850 to +540 ADD20 of observed PMI. Test set 2 had poor predictions for two CDIs, for all measures of postmortem indices resulting in discussion of sampling depth, effect of body mass index (BMI), and scavenging.

Comparing the Scoring of Human Decomposition from Digital Images to Scoring Using On-site Observations.

When in forensic casework or empirical research in-person assessment of human decomposition is not possible, the sensible substitution is color photographic images. To date, no research has confirmed the utility of color photographic images as a proxy for in situ observation of the level of decomposition. Sixteen observers scored photographs of 13 human cadavers in varying decomposition stages (PMI 2-186 days) using the Total Body Score system (total n = 929 observations). The on-site TBS was compared with recorded observations from digital color images using a paired samples t-test. The average difference between on-site and photographic observations was -0.20 (t = -1.679, df = 928, p = 0.094). Individually, only two observers, both students with <1 year of experience, demonstrated TBS statistically significantly different than the on-site value, suggesting that with experience, observations of human decomposition based on digital images can be substituted for assessments based on observation of the corpse in situ, when necessary.

Interobserver Reliability of the Total Body Score System for Quantifying Human Decomposition.

Several authors have tested the accuracy of the Total Body Score (TBS) method for quantifying decomposition, but none have examined the reliability of the method as a scoring system by testing interobserver error rates. Sixteen participants used the TBS system to score 59 observation packets including photographs and written descriptions of 13 human cadavers in different stages of decomposition (postmortem interval: 2-186 days). Data analysis used a two-way random model intraclass correlation in SPSS (v. 17.0). The TBS method showed "almost perfect" agreement between observers, with average absolute correlation coefficients of 0.990 and average consistency correlation coefficients of 0.991. While the TBS method may have sources of error, scoring reliability is not one of them. Individual component scores were examined, and the influences of education and experience levels were investigated. Overall, the trunk component scores were the least concordant. Suggestions are made to improve the reliability of the TBS method.

A hydrologic retention system and water quality monitoring program for a human decomposition research facility: concept and design.

Forensic taphonomy is an essential research field; however, the decomposition of human cadavers at forensic science facilities may lead to nutrient loading and the introduction of unique biological compounds to adjacent areas. The infrastructure of a water retention system may provide a mechanism for the biogeochemical processing and retention of nutrients and compounds, ensuring the control of runoff from forensic facilities. This work provides a proof of concept for a hydrologic retention system and an autonomous water quality monitoring program designed to mitigate runoff from The Southeast Texas Applied Forensic Science (STAFS) Facility. Water samples collected along a sample transect were analyzed for total phosphorous, total nitrogen, NO3-, NO2-, NH4, F(-), and Cl(-). Preliminary water quality analyses confirm the overall effectiveness of the water retention system. These results are discussed with relation to how this infrastructure can be expanded upon to monitor additional, more novel, byproducts of forensic science research facilities.

Determining postmortem interval using glycoproteinous adhesion deposits by Balanus improvisus on human skeletal and dental remains.

An anthropological analysis was conducted on skeletal and dental remains brought to the Galveston County Medical Examiner's office. The skeletal remains were dry, fragmented, and absent of typical fluvial characteristics. During microscopic examination, semitransparent, circular objects were discovered on the dentition, the mandible, tibial plateau, and distal femur. The objects were glycoproteinous adhesions deposited by the acorn barnacle, Balanus improvisus. B. improvisus is an intertidal barnacle found in estuaries in Galveston Bay. Basal diameter of the adhesions on the dentition were significantly smaller than those found on the postcranial bones (p = 0.010), indicating two consecutive cohorts adhered to the bone and dentition. As settlement typically occurs once a year, this would indicate that the remains were in the fluvial environment for at least 375-410 days. It is important in geographic areas that have prevalent fluvial environments that human remains, particularly dentition, are microscopically examined for marine life evidence.

Scavenging behavior of Lynx rufus on human remains during the winter months of Southeast Texas.

Animal-scavenging alterations on human remains can be mistaken as human criminal activity. A 32-day study, documenting animal scavenging on a human cadaver, was conducted at the Southeast Texas Applied Forensic Science facility, Sam Houston State University, Huntsville, Texas. A Stealth Cam Rogue IR was positioned near the cadaver to capture scavenging activity. An atypical scavenger, the bobcat, Lynx rufus, was recorded feeding on the cadaver. Scavenging by bobcats on human remains is not a predominant behavior and has minimal documentation. Scavenging behaviors and destruction of body tissues were analyzed. Results show that the bobcat did not feed on areas of the body that it does for other large animal carcasses. Results also show the bobcat feeds similarly during peak and nonpeak hours. Understanding the destruction of human tissue and covering of the body with leaf debris may aid forensic anthropologists and pathologists in differentiating between nefarious human activity and animal scavenging.

Exclusion of forensically important flies due to burying behavior by the red imported fire ant (Solenopsis invicta) in southeast Texas.

On March 3, 2009, the remains of an adult male were partially buried at the Southeast Texas Applied Forensic Science (STAFS) Facility at the Center for Biological Field Studies (CBFS), Sam Houston State University, Texas. The individual was buried except for a small portion of the left abdominal region. A postmortem incised wound was created in the exposed area with the intention of attracting carrion flies. Worker ants of a colony of Solenopsis invicta Buren 1972 (red imported fire ant) filled in the wound with soil, thereby monopolizing the exposed area of the corpse and excluding expected carrion insects from the wound. During the bloating phase, approximately nine days after burial, normal decomposition processes of the gut created a sufficient disruption of the ants, such that flies oviposited and larvae were able to colonize the corpse. Estimation of the postmortem interval (PMI) based on the minimum period of fly activity would be severely skewed should the remains be discovered at this point and growth rate of Diptera larvae be used as the primary determinant for the PMI. While S. invicta is an expected member of a carrion ecosystem in southeastern Texas, and is known to distort the PMI estimation through larval and egg removal, the complete exclusion of flies from the wound by the burial behavior of S. invicta was an unexpected and until now an unpublished occurrence.

A geometric morphometric approach to sex determination of the human adult os coxa.

Sex determination of the human skeleton is best assessed from the os coxa. The present study explored the possibility of using three-dimensional landmark coordinate data collected from various landmarks located over the entire bone to determine whether there were significant sex differences local to the landmarks. Thirty-six landmarks were digitized on 200 African American and European American male and female adult human os coxae. MANCOVA results show that sex and size have a significant effect on shape for both European Americans (Sex, F = 17.50, d.f. = 36, 63, p > F = 0.0001; Size, F = 2.56, d.f. = 36, 63, p > F = 0.0022) and African Americans (Sex, F = 21.18, d.f. = 36, 63, p > F = 0.0001; Size, F = 2.59, d.f. = 36, 63, p > F = 0.0005). The discriminant analysis shows that sexing accuracy for European Americans is 98% for both males and females, 98% for African American females, and 100% for African American males.

Necrophagous caterpillars provide human mtDNA evidence.

Decomposition of large mammalian carcasses is greatly accelerated through the action of insects. Specialized feeders capable of digesting keratin and collagen found in skin, hair, and tendons and ligaments are attracted to corpses in late stages of dry decomposition and include Tinea pellionella, the casemaking clothes moth, and Tineola bisselliella, the webbing clothes moth (Lepidoptera; Tineidae). Until now, details of the caterpillar behavior as necrophagous insects were vague. Here, we detail the behavior of each species and document the incorporation of human hair into the portable larval shelters constructed by the caterpillars of T. pellionella. Hair of the decedent used as building material for caterpillar shelters provided enough starting template to amplify and sequence the HVI and HVII sections of the control region (mtDNA) of the decedent.

Insect successional pattern of a corpse in cooler months of subtropical southeastern Texas.

Here, we characterize the cool weather insect fauna found associated with partially skeletonized and desiccated human remains recovered from an abandoned house in an urban area of subtropical, coastal Galveston County, Texas, and use the information to conclude an approximate postmortem interval of 7-10 months. The predominant factors that allow for a confident assessment of the postmortem interval include climatological data, entomological data, and anthropological data. The documented insect fauna represents a unique assemblage present in a particular environment (an urban abandoned house in coastal Texas) at a particular time of year (winter) and includes expected forensically significant insects such as calliphorid flies, muscid flies, and dermestid beetles but also includes less commonly encountered insects such as an unusually dense population of live case-making clothes moths.