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J Indian Acad Forensic Med. October- December 2011, Vol. 33, No. 4 ISSN 0971-0973 Original Research Paper Effect of Ageing & Environmental Condition for Detection of Blood Group from Blood Stain *Prakash M. Mohite, **Atul Keche, ***Anil J. Anjankar, ****Sudhir Ninave Abstract It is an established fact that laboratory investigations involving biological fluids play a vital role in crime investigations Blood as a source of evidence associated with crime, can provide valuable information that may solve the case. Proper collection, preservation and dispatch of this crucial evidence to the Forensic Science Laboratory is hence very essential. Improper collection and preservation can weaken or destroy a potential source of facts in a case. Many times the suspects may hide valuable blood stain evidence either on the object or the clothes in different conditions which may adversely affect the investigation. Hence, proper collection and preservation of blood stain is of paramount importance, as it may provide a strong link between an individual and a criminal act. The present study was undertaken to find out the maximum duration for which blood grouping is possible when the stains are exposed to varied environmental conditions. Key Words: Blood Stain, Evidence, Blood grouping, Crime scene. Introduction It is an established fact that laboratory investigations involving biological fluids play a vital role in crime investigations. It is useful scientific evidence as it forms an important link in chain of evidence or supports circumstantial evidence. [1] Edmond Locard (1877-1966), a lawyer and a physician, proposed that every criminal carries some elements with him/ her from the scene of crime by which he / she can be linked with the crime. Blood and Blood stains, likewise are a very important entity in medico legal practices, as factors like source of blood and their stains help in solving the crime of Violence, Sexual offences , Vehicular accident cases, Disasters etc. [1] It helps to establish the relation between the offence, offender, the offended and the offending agent. A careful preservation of Blood samples and blood stain is therefore important. A careful laboratory investigation of Blood and Blood stain can yield information useful in the court of law with a varying degree of reliability. [2] Blood stains may be present on any material. Environmental changes affect its morphology & its contents. Corresponding Author: *Professor, Department of Forensic Medicine, Jawaharlal Nehru Medical College, Sawangi (Meghe), Wardha (M.S) 442 004. ** Assistant Professor *** Professor & Head **** Associate Professor 308 Last but not the least the time lapse from its occurrence to its examination is also an important factor. Hence it was thought appropriate to take up the study to find out the effect of ageing and environmental factors on blood stains. Material & Methodology: This study was carried out in the Department of Forensic Medicine Jawaharlal Nehru Medical College, Sawangi (meghe) Wardha over a period of 3 years. For the study stains were prepared on different fabrics like Cotton cloth, terelene cloth and cotton gauze pieces of 2" x2" size. Known blood group samples were taken from the blood bank, Department of Pathology, where grouping of samples is done before transfusion. With the known blood group, stains were prepared by putting a drop of blood with the help of dropper over the cut pieces of fabrics with blood spread evenly on all parts of the fabric. The stains prepared were labeled (known group and with date on which it was prepared) and were subjected to different environmental conditions. Stains prepared on each fabric were equally divided and were kept in five different conditions. The stains, so prepared were stored in five (5) different conditions as under: 1. Moist: Immediately wrapped in plain paper or kept in zip locked polythene bag. 2. Semi moist: Stain was allowed to dry for 6-8 hours at room temperature and then wrapped in plain paper or zip polythene bag. 3. Dry: Stains were completely dried at room temperature under normal condition and
J Indian Acad Forensic Med. October- December 2011, Vol. 33, No. 4 ISSN 0971-0973 then wrapped in plain paper or zip polythene bag. 4. Air dried: Stain was kept directly in front of fan to dry and then stored. 5. Heat dried: Stains were dried using indirect heat e.g. by keeping near the heater and then wrapped. Stains belonging to each group were then stored in different environmental conditions: one in the refrigerator at 4-6 ° C temperature and another at room temperature, which varied from 9.4 ° C to 46 ° C during the period of study. These stains were then examined at fixed and regular intervals of time (Weekly) using absorption elution method, which is the most common technique used and the observations were noted. Observations: In the present study stain prepared on different fabric and exposed to different environmental conditions before wrapping, were examined after every seven (7) days and result for clumping of cells were noted by absorption elution method. Clear clumping of cells was taken as positive result while any doubt about the clumping of cells due to any reason was taken as inconclusive result. On regular and fixed interval of time, stain examination for blood grouping, it is observed that stains kept in conditions like moist condition, air dried or heat dried prepared on cotton gauze and terelene cloth, gives positive result upto 6 weeks after that results were inconclusive. While on cotton cloth stains exposed to same conditions gives positive result up to 10 weeks. (Figure 1) Whereas stains prepared on all these 3 fabrics and wrapped in semi moist condition the detection of blood group on stain examination is positive for a longer duration i.e. up to 1 year, irrespective of the fabric. Similarly the stains prepared on these 3 fabrics if dried completely at room temperature in normal conditions (without using artificial means for drying) and kept at room temperature the result vary on different fabrics, the stain on terelene cloth gives positive result up to 18-20 months i.e. (up to 1 ½ years) , stain on cotton gauze piece gives positive result up to 24-26 months i.e. ( up to 2 years) and the stains on cotton cloth it is observed that the result is positive up to 3 years, the maximum period for which the study is carried out. (Figure 2) Overall stains examined, kept under different environment conditions made on different fabrics shows positive result up to 6 months in moist condition, up to 1 year in semi moist condition & up to 3 yrs in stains kept at 309 room temperature in normal condition. (Figure 3) Discussion: Detection of blood group on blood stain examination depends on various factors like on which substrata that stain is present or how the blood stain was preserved whether the stain was exposed to extreme temperature, direct sunlight or was the stain dried using fan or indirect heat using heater. And at what interval of time the stain is examined after preserving, whether the stain was kept at room temperature or was it refrigerated or frozen if stain is not dispatch to the concerned forensic science laboratory immediately. In the present study, all these factors were taken into consideration and study was carried out on different parameters as stains were prepared on different fabrics like cotton cloth piece, cotton gauze piece and terelene cloth piece and were exposed to different environment conditions i.e. stains were either air dried, kept at 4-6 0 c temperature or in moist condition wet before packing in poly zip bag or paper envelop and then examined at different interval of time. In this study it was found that stains which were allowed to dry naturally at room temperature and then wrapped in paper envelop or zip poly bag gives positive result up to 3 years on cotton cloth ,which is observed by James et al. & others. The stains which were either wrapped in moist conditions or dried using fan or heat shows positive result upto 6-10 weeks as heat if applied to the blood stain, causes physical changes within the blood stain.3In the present study all the stains dried using fan or heat on any fibre shows inconclusive results after 10 weeks as fan blows foreign material onto the stain leading to contamination & gives inconclusive result. [4] Grouping on the dried blood stain is more difficult. The time lapse, exposure to direct sunlight, extreme temperature and other natural conditions yield changes that reduces the possibility of successful grouping of the blood stain. In this study all the stains which were moist (wet) & semi moist i.e. kept at 4-6 0c before wrapping in the paper envelop or poly zip bag shows positive result up to 6 weeks in cotton gauze & terelene cloth pieces & up to 10 weeks on cotton cloth piece. Dry Stains on cotton cloth piece gives positive result up to 3 years while on cotton gauze up to 2 year & on terelene up to 1 ½ year. Conclusion: It is concluded that blood stain should be dried properly. Blood stain should not be
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